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Expressions-with-variables/227843: x + y = 7
x + 3y = 11
1 solutions

Answer 169270 by drj(1380) About Me  on 2009-10-17 11:59:00 (Show Source):
You can put this solution on YOUR website!
x+%2B+y+=+7 Equation A
x+%2B+3y+=+11 Equation B

Step 1. Subtract Equation A from Equation B (or Equation B - Equation A) to eliminate x

x-x%2B3y-y=11-7

2y=4

Step 2. Divide by 2 to both sides of the equation

2y%2F2=4%2F2

y=2

Step 3. Now Substitute y=2 into equation A x+%2B+y+=+7 to find x

x%2B2=7

Subtract 2 from both sides to get x.

x%2B2-2=7-2

x=5

Step 4. Now we have x=5 and y=2 as a solution. Check to see if this also satisfies equation B x+%2B+3y+=+11.

5%2B3%2A2=11

11=11 which is a true statement

Step 5. ANSWER: The solution is x=5 and y=2. Or the intersection point between these two lines is (5,2). See graph below,

graph%28400%2C400%2C+-10%2C+10%2C+-10%2C+10%2C+-x%2B7%2C+-x%2F3%2B11%2F3%29

I hope the above steps were helpful.

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J

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Equations/227868: 4r-3=5+3r
1 solutions

Answer 169269 by drj(1380) About Me  on 2009-10-17 11:48:26 (Show Source):
You can put this solution on YOUR website!
4r-3=5%2B3r

Step 1. Goal is to get only numbers on one side and the variable on the other side of the equation. First, subtract 3r from both sides of the equation to put the variable r in the left side.

4r-3-3r=5%2B3r-3r

r-3=5

Step 2. Add 3 to both sides of the equation to isolate r by itself and you'll have numbers only on the right side.

r-3%2B3=5%2B3

r=8

Step 3. Now, check solution r=8 by substituting into the original given equation 4r-3=5%2B3r and see if it leads to a true statement.

4%2A8-3=5%2B3%2A8

32-3=5%2B24

29=29 which is a true statement.

Step 4. ANSWER: The solution is r=8

I hope the above steps were helpful.

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J


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Equations/227853: 5x+3y=12
8x+3y=9
1 solutions

Answer 169267 by drj(1380) About Me  on 2009-10-17 11:39:33 (Show Source):
You can put this solution on YOUR website!
5x+3y=12
8x+3y=9

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++5%5Cx+%2B+3%5Cy+=+12%2C%0D%0A++++8%5Cx+%2B+3%5Cy+=+9+%29%0D%0A++We'll use substitution. After moving 3*y to the right, we get:
5%2Ax+=+12+-+3%2Ay, or x+=+12%2F5+-+3%2Ay%2F5. Substitute that
into another equation:
8%2A%2812%2F5+-+3%2Ay%2F5%29+%2B+3%5Cy+=+9 and simplify: Error: 'Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. '. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115.
error_location: 101



I hope the above steps were helpful.

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J


http://www.FreedomUniversity.TV
http://www.Facebook.com/FreedomUniversity.TV
http://www.Twitter.com/FreedomUTV

Rectangles/227779: Suppose that the length of a rectangle is three cm longer than twice the width and that the perimeter of the rectangle is 90 cm.Set up an equation for the perimeter involving only W, the width of the rectangle. “On The Question About The Rectangle Being 90 Centimeters, I Also Was Needing The Equation Algebraically To Find Length Of The Rectangle And The Width As Well?
1 solutions

Answer 169229 by drj(1380) About Me  on 2009-10-17 00:42:17 (Show Source):
You can put this solution on YOUR website!
Suppose that the length of a rectangle is three cm longer than twice the width and that the perimeter of the rectangle is 90 cm. Set up an equation for the perimeter involving only W, the width of the rectangle. “On The Question About The Rectangle Being 90 Centimeters, I Also Was Needing The Equation Algebraically To Find Length Of The Rectangle And The Width As Well?

Step 1. The perimeter P means adding up all the four sides of a rectangle.

Step 2. Let w be the width.

Step 3. Let 2w+3 be the length since the length is three cm longer than twice the width.

Step 4. Then, P=w+w+2w+3+2w+3=90.

Step 5. Solving yields the following steps

6w%2B6=90

Subtract 6 from both sides of the equation

6w%2B6-6=90-6

6w=84

Divide by 6 to both sides of the equation

6w%2F6=84%2F6

w=14

For w=14 , then 2w%2B3=31 and P=2(14+31)=90 which is a true statement.

Step 6. ANSWER: The width is 14 cm and the length is 31 cm.

I hope the above steps were helpful.

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J

drjctu@gmail.com

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Equations/227780: Can you help me Solve the problem by using addition/elimination?
1.8x-2y=0.9
0.04x+0.18y=0.15
1 solutions

Answer 169228 by drj(1380) About Me  on 2009-10-17 00:31:13 (Show Source):
You can put this solution on YOUR website!
Can someone pls show me how to solve this equation using the addition/elimination process?

1.8x-2y=0.9 Equation A
0.04x+0.18y=0.15 Equation B

Step 1. Multiply by 0.09 to Equation A to both sides of the equation

0.162x-0.18y=0.081 Equation A1
0.04x%2B0.18y=0.15 Equation B
Step 2. Add Equations A1 and B to eliminate the y terms.

0.162x%2B0.04x-0.18y%2B0.18y=0.081%2B0.15

0.202x=0.231

Step 3. Divide by 0.202 to both sides of the equation

0.202x%2F0.202=0.231%2F0.202

x=1.143

Step 4. Substitute x=1.143 into Equation A 1.8x-2y=0.9 to solve for y.

1.8%2A1.143-2y=0.9

2.0584-2y=0.9

Step 5. Add 2y-0.9 to both sides of the equation

2.0584-2y%2B2y-0.9=0.9%2B2y-0.9

1.1584=2y

Step 6. Divide by 2 to both sides of the equation

y=0.5792

Step 7. ANSWER: The solution is x=1.143 and y=0.5792

As a check, use the substitution shown below which have the same results.

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
We'll use substitution. After moving -2*y to the right, we get:
1.8%2Ax+=+0.9+-+-2%2Ay, or x+=+0.9%2F1.8+-+-2%2Ay%2F1.8. Substitute that
into another equation:
0.04%2A%280.9%2F1.8+-+-2%2Ay%2F1.8%29+%2B+0.18%5Cy+=+0.15 and simplify: Error: 'Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. '. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115.
error_location: 101


I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV






Equations/227783: How do I sovle the system?
2x+5y=1
-x+6y=8
1 solutions

Answer 169226 by drj(1380) About Me  on 2009-10-17 00:28:16 (Show Source):
You can put this solution on YOUR website!
How do I solve the system?
2x+5y=1
-x+6y=8

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++2%5Cx+%2B+5%5Cy+=+1%2C%0D%0A++++-1%5Cx+%2B+6%5Cy+=+8+%29%0D%0A++We'll use substitution. After moving 5*y to the right, we get:
2%2Ax+=+1+-+5%2Ay, or x+=+1%2F2+-+5%2Ay%2F2. Substitute that
into another equation:
-1%2A%281%2F2+-+5%2Ay%2F2%29+%2B+6%5Cy+=+8 and simplify: Error: 'Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. '. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115.
error_location: 101



I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV


Equations/227782: How would I solve for x?
-3x+6(x+4)=9
1 solutions

Answer 169225 by drj(1380) About Me  on 2009-10-17 00:25:19 (Show Source):
You can put this solution on YOUR website!
How would I solve for x?

-3x%2B6%28x%2B4%29=9

Step 1. Multiply to get rid of the parenthesis.

-3x%2B6x%2B24=9

Step 2. Combine x-terms

3x%2B24=9

Step 3. Subtract 24 from both sides of the equation

3x%2B24-24=9-24

3x=-15

Step 4. Divide by 3 to both sides of the equation

3x%2F3=-15%2F3

x=-5

Step 5. Substitute x=5 into the original equation -3x%2B6%28x%2B4%29=9 to check solution.

-3%2A%28-5%29%2B6%28-5%2B4%29=9

15%2B%28-6%29=9

9=9 which is a true statement.

Step 6. ANSWER: Solution is x=-5.

I hope the above steps were helpful.

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV


Evaluation_Word_Problems/227778: The perimeter of a rectangle is 106 inches. The length exceeds the width by 45 inches. Find the length and the width.
The length is ____ inches.
(Type an integer or a decimal)

1 solutions

Answer 169224 by drj(1380) About Me  on 2009-10-17 00:13:53 (Show Source):
You can put this solution on YOUR website!
The perimeter of a rectangle is 106 inches. The length exceeds the width by 45 inches. Find the length and the width.

The length is 49 inches.

(Type an integer or a decimal)

Step 1. The perimeter P means adding up all the four sides of a rectangle.

Step 2. Let w be the width.

Step 3. Let w+45 be the length

Step 4. Then, P=w+w+w+45+w+45=106.

Step 5. Solving yields the following steps

4w%2B90=106

Subtract 90 form both sides of the equation

4w%2B90-90=106-90

4w=16

Divide by 4 to both sides of the equation.

4w%2F4=16%2F4

w=4

For w=4 , then w%2B4=49 and check P=2%284%2B49%29=106 which is a true statement.

Step 6. ANSWER: The length is 49 inches.

I hope the above steps were helpful.

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J


Geometry_Word_Problems/227769: PLEASE HELP ME SOLVE THESE PROBLEMS:
1. A SQUARE AND RECTANGLE HAVE EQUAL AREAS. IF THE RECTANGLE IS 36 BY 16, WHAT IS THE SIDE OF A SQUARE?
2.IN A SOCIAL HALL OF A BUILDING, THERE ARE 150 SEATS ARRANGED IN ROWS WITH 5 MORE SEATS PER ROW THAN THE NUMBER OF ROWS. HOW MANY SEATS ARE THERE IN EACH ROW?
THANK YOU!!! I REALLY APPRECIATE IT...
1 solutions

Answer 169223 by drj(1380) About Me  on 2009-10-16 23:16:01 (Show Source):
You can put this solution on YOUR website!
Problem 1. A SQUARE AND RECTANGLE HAVE EQUAL AREAS. IF THE RECTANGLE IS 36 BY 16, WHAT IS THE SIDE OF A SQUARE?

Step 1. The area of a rectangle A=36*16=576 (area=base*height}}}

Step 2. The square has equal sides where we let s be the side which is equal to the base and height so A=s*s=s^2.

Step 3. The areas are equal in Steps 1 and 2. Then s%5E2=576

Step 4. Take the square root to both sides of the equation or s=24.

Step 5. ANSWER: The side of the square is 24.

Problem 2. IN A SOCIAL HALL OF A BUILDING, THERE ARE 150 SEATS ARRANGED IN ROWS WITH 5 MORE SEATS PER ROW THAN THE NUMBER OF ROWS. HOW MANY SEATS ARE THERE IN EACH ROW?

Step 1. Let n be the number of rows.

Step 2. Let n+5 be the number of seats per row.

Step 3. Then, n(n+5)=150 since there are 150 seats.

Step 4. Subtract 150 to both sides of equation in Step 3.

n%5E2%2B5n-150=150%2B150

n%5E2%2B5n-150=0

Step 5. To solve, use the quadratic equation given as

x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

where a=1, b=5, and c=-150

Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation an%5E2%2Bbn%2Bc=0 (in our case 1n%5E2%2B5n%2B-150+=+0) has the following solutons:

n%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%285%29%5E2-4%2A1%2A-150=625.

Discriminant d=625 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-5%2B-sqrt%28+625+%29%29%2F2%5Ca.

n%5B1%5D+=+%28-%285%29%2Bsqrt%28+625+%29%29%2F2%5C1+=+10
n%5B2%5D+=+%28-%285%29-sqrt%28+625+%29%29%2F2%5C1+=+-15

Quadratic expression 1n%5E2%2B5n%2B-150 can be factored:
1n%5E2%2B5n%2B-150+=+1%28n-10%29%2A%28n--15%29
Again, the answer is: 10, -15. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B5%2Ax%2B-150+%29



Selecting the positive solution of n=10 and n%2B5=15 and note the product is 150 seats.

Step 6. ANSWER: The number of seats in each row is 15 seats.

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV




Age_Word_Problems/227765: Five years ago. Jhons age was half of the age he will be in 8 years. How old is he now?



1 solutions

Answer 169222 by drj(1380) About Me  on 2009-10-16 22:52:59 (Show Source):
You can put this solution on YOUR website!
Five years ago, Jhons age was half of the age he will be in 8 years. How old is he now?

Step 1. Let x be the age of Jhons.

Step 2. Let x-5 be the age of Jhons five years ago.

Step 3. Let x+8 be the age of Jhons 8 years from now.

Step 4. Then x-5=%28x%2B8%29%2F2 since five years ago, Jhons age was half of the age he will be in 8 years

Step 5. Solving the equation in Step 4 yields the following steps

Multiply by 2 to get rid of the denominator

2%2A%28x-5%29=2%2A%28x%2B8%29%2F2

2x-10=x%2B8

Add 10-x to both sides of the equation

2x-10%2B10-x=x%2B8%2B10-x

x=18

Check equation in Step 4 x-5=%28x%2B8%29%2F2 or 18-5=%2818%2B8%29%2F2. Then 13=13 which is a true statement.

Step 6. ANSWER: The age of Jhons is 18 years old.

I hope the above steps were helpful.

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J

drjctu@gmail.com

http://www.FreedomUniversity.TV
http://www.Facebook.com/FreedomUniversity.TV
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Linear-equations/227768: 1. By looking at two linear equations, is there a way you can you tell if the corresponding lines are parallel?
1 solutions

Answer 169220 by drj(1380) About Me  on 2009-10-16 22:43:58 (Show Source):
You can put this solution on YOUR website!
By looking at two linear equations, is there a way you can you tell if the corresponding lines are parallel?

Step 1. Two lines are parallel when they have the same slope, say m.

Step 2. So the two linear equations should be in slope-intercept form given as y=mx+b where m is the slope and b is the y-intercept when x=0 or at point (0,b).

Step 3. Example: y=2x+3 and y=2x-9. These two line are parallel since the slope is m=2.

I hope the above steps were helpful.

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J

drjctu@gmail.com

http://www.FreedomUniversity.TV
http://www.Facebook.com/FreedomUniversity.TV
http://www.Twitter.com/FreedomUTV


Polynomials-and-rational-expressions/227759: What is the LCM of 5(x-3) and 15(x-3).
1 solutions

Answer 169219 by drj(1380) About Me  on 2009-10-16 22:40:07 (Show Source):
You can put this solution on YOUR website!
What is the LCM of 5(x-3) and 15(x-3).

Step 1. The Least Common Multiple is the smallest number that is a multiple of two or more numbers.

Step 2. In this example, looking first at the numbers, the Least Common Multiple of 5 and 15 is 15, because 15 is a multiple of 15 and also a multiple of 5.

Step 3. Also x-3 is the least common multiple between the two terms.

Step 4. ANSWER: The LCM is 15(x-3).

I hope the above steps were helpful.

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV
http://www.Facebook.com/FreedomUniversity.TV
http://www.Twitter.com/FreedomUTV


Rectangles/227757: Suppose that the length of a rectangle is three cm longer than twice the width and that the perimeter of the rectangle is 90 cm.
a) Set up an equation for the perimeter involving only W, the width of the rectangle.

1 solutions

Answer 169217 by drj(1380) About Me  on 2009-10-16 22:33:38 (Show Source):
You can put this solution on YOUR website!
Suppose that the length of a rectangle is three cm longer than twice the width and that the perimeter of the rectangle is 90 cm.

Step 1. The perimeter P means adding up all the four sides of a rectangle.

Step 2. Let w be the width.

Step 3. Let 2w+3 be the length since the length is three cm longer than twice the width.

Step 4. Then, P=w+w+2w+3+2w+3=90.

Step 5. Solving yields the following steps

Solved by pluggable solver: EXPLAIN simplification of an expression
Your Result:


YOUR ANSWER


  • Here's what you tried:
  • This is an equation! Solutions: w=14.
  • Graphical form: Equation w%2Bw%2B2w%2B3%2B2w%2B3=90 was fully solved.
  • Text form: w+w+2w+3+2w+3=90 simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+w%2Bw%2B2w%2B3%2B2w%2B3=90+%29
    For tutors: simplify_cartoon( w+w+2w+3+2w+3=90 )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at w%2Bw%2B2%2Aw%2Bhighlight_red%28+3+%29%2B2%2Aw%2Bhighlight_red%28+3+%29=90.
Added fractions or integers together
It becomes w%2Bw%2B2%2Aw%2Bhighlight_green%28+6+%29%2B2%2Aw=90.

Look at w%2Bw%2B2%2Aw%2Bhighlight_red%28+6+%29%2B2%2Aw=90.
Moved 6 to the right of expression
It becomes w%2Bw%2B2%2Aw%2B2%2Aw%2Bhighlight_green%28+6+%29=90.

Look at .
Eliminated similar terms highlight_red%28+w+%29,highlight_red%28+w+%29,highlight_red%28+2%2Aw+%29,highlight_red%28+2%2Aw+%29 replacing them with highlight_green%28+%281%2B1%2B2%2B2%29%2Aw+%29
It becomes highlight_green%28+%281%2B1%2B2%2B2%29%2Aw+%29%2B6=90.

Look at .
Added fractions or integers together
It becomes %28highlight_green%28+6+%29%29%2Aw%2B6=90.

Look at highlight_red%28+%28highlight_red%28+6+%29%29%2Aw+%29%2B6=90.
Remove unneeded parentheses around factor highlight_red%28+6+%29
It becomes highlight_green%28+6+%29%2Aw%2B6=90.

Look at 6%2Aw%2B6=highlight_red%28+90+%29.
Moved these terms to the left highlight_green%28+-90+%29
It becomes 6%2Aw%2B6-highlight_green%28+90+%29=0.

Look at 6%2Aw%2Bhighlight_red%28+6+%29-highlight_red%28+90+%29=0.
Added fractions or integers together
It becomes 6%2Aw%2Bhighlight_green%28+-84+%29=0.

Look at 6%2Aw%2Bhighlight_red%28+-84+%29=0.
Removed extra sign in front of -84
It becomes 6%2Aw-highlight_green%28+84+%29=0.

Look at highlight_red%28+6%2Aw-84+%29=0.
Solved linear equation highlight_red%28+6%2Aw-84=0+%29 equivalent to 6*w-84 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: w=14.

Universal Simplifier and Solver


Done!



For w=14 , then 2w+3=31 and P=2(14+31)=90 which is a true statement.

Step 6. ANSWER: The width is 14 cm and the length is 31 cm.

I hope the above steps were helpful.

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J

drjctu@gmail.com

http://www.FreedomUniversity.TV
http://www.Facebook.com/FreedomUniversity.TV
http://www.Twitter.com/FreedomUTVep 1. Let w be the width


Linear-equations/227731: The perimeter of a rectangle is 70 m. The length is 8 meters more than twice the width. Find the length and width.
Thank you in advance.
1 solutions

Answer 169215 by drj(1380) About Me  on 2009-10-16 22:16:39 (Show Source):
You can put this solution on YOUR website!
The perimeter of a rectangle is 70 m. The length is 8 meters more than twice the width. Find the length and width.

Step 1. The perimeter P means adding up all the four sides of a rectangle.

Step 2. Let w be the width.

Step 3. Let 2w+8 be the length since the length is 8 meters more than twice the width

Step 4. Then, P=w+w+2w+8+2w+8=70.

Step 5. Solving yields the following steps

Solved by pluggable solver: EXPLAIN simplification of an expression
Your Result:


YOUR ANSWER


  • Here's what you tried:
  • This is an equation! Solutions: w=9.
  • Graphical form: Equation w%2Bw%2B2w%2B8%2B2w%2B8=70 was fully solved.
  • Text form: w+w+2w+8+2w+8=70 simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+w%2Bw%2B2w%2B8%2B2w%2B8=70+%29
    For tutors: simplify_cartoon( w+w+2w+8+2w+8=70 )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at w%2Bw%2B2%2Aw%2Bhighlight_red%28+8+%29%2B2%2Aw%2Bhighlight_red%28+8+%29=70.
Added fractions or integers together
It becomes w%2Bw%2B2%2Aw%2Bhighlight_green%28+16+%29%2B2%2Aw=70.

Look at w%2Bw%2B2%2Aw%2Bhighlight_red%28+16+%29%2B2%2Aw=70.
Moved 16 to the right of expression
It becomes w%2Bw%2B2%2Aw%2B2%2Aw%2Bhighlight_green%28+16+%29=70.

Look at .
Eliminated similar terms highlight_red%28+w+%29,highlight_red%28+w+%29,highlight_red%28+2%2Aw+%29,highlight_red%28+2%2Aw+%29 replacing them with highlight_green%28+%281%2B1%2B2%2B2%29%2Aw+%29
It becomes highlight_green%28+%281%2B1%2B2%2B2%29%2Aw+%29%2B16=70.

Look at .
Added fractions or integers together
It becomes %28highlight_green%28+6+%29%29%2Aw%2B16=70.

Look at highlight_red%28+%28highlight_red%28+6+%29%29%2Aw+%29%2B16=70.
Remove unneeded parentheses around factor highlight_red%28+6+%29
It becomes highlight_green%28+6+%29%2Aw%2B16=70.

Look at 6%2Aw%2B16=highlight_red%28+70+%29.
Moved these terms to the left highlight_green%28+-70+%29
It becomes 6%2Aw%2B16-highlight_green%28+70+%29=0.

Look at 6%2Aw%2Bhighlight_red%28+16+%29-highlight_red%28+70+%29=0.
Added fractions or integers together
It becomes 6%2Aw%2Bhighlight_green%28+-54+%29=0.

Look at 6%2Aw%2Bhighlight_red%28+-54+%29=0.
Removed extra sign in front of -54
It becomes 6%2Aw-highlight_green%28+54+%29=0.

Look at highlight_red%28+6%2Aw-54+%29=0.
Solved linear equation highlight_red%28+6%2Aw-54=0+%29 equivalent to 6*w-54 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: w=9.

Universal Simplifier and Solver


Done!



For w=9 , then 2w+8=26 and P=2(9+26)=70 which is a true statement.

Step 6. ANSWER: The width is 9 meters and length is 26 meters.

I hope the above steps were helpful.

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV
http://www.Facebook.com/FreedomUniversity.TV
http://www.Twitter.com/FreedomUTV


Equations/227752: Can you help me solve this equation by substitution?
8x+2y=6
4x=3-y
1 solutions

Answer 169214 by drj(1380) About Me  on 2009-10-16 22:12:18 (Show Source):
You can put this solution on YOUR website!
Can you help me solve this equation by substitution?

8x+2y=6
4x=3-y or 4x+y=3

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++8%5Cx+%2B+2%5Cy+=+6%2C%0D%0A++++4%5Cx+%2B+1%5Cy+=+3+%29%0D%0A++We'll use substitution. After moving 2*y to the right, we get:
8%2Ax+=+6+-+2%2Ay, or x+=+6%2F8+-+2%2Ay%2F8. Substitute that
into another equation:
4%2A%286%2F8+-+2%2Ay%2F8%29+%2B+1%5Cy+=+3 and simplify: Error: 'Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. '. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115.
error_location: 101



I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV

Rectangles/227743: Find an algebraic expression. The perimeter of a rectangle, given that the length is x yards and the width is 10 yards shorter.
1 solutions

Answer 169213 by drj(1380) About Me  on 2009-10-16 22:10:24 (Show Source):
You can put this solution on YOUR website!
Find an algebraic expression. The perimeter of a rectangle, given that the length is x yards and the width is 10 yards shorter.

Step 1. Perimeter P means adding up all four sides of the rectangle.

Step 2. x-10 be the width of the rectangle since the width is 10 yards shorter.

Step 3. P=x+x+x-10+x-10=4x-20

Step 4. ANSWER: Perimeter P=4x-20 (in yards).

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV


Rate-of-work-word-problems/227749: A picture 8 inches long and 6 inches wide is to be enlarged so that its length will be 12 inches. What is the width in inches, of the enlarged picture?
a.6
b. 3
c. 2
4. 8
5.9
1 solutions

Answer 169212 by drj(1380) About Me  on 2009-10-16 22:06:38 (Show Source):
You can put this solution on YOUR website!
A picture 8 inches long and 6 inches wide is to be enlarged so that its length will be 12 inches. What is the width in inches, of the enlarged picture?

a.6
b. 3
c. 2
4. 8
5.9

Step 1. Assume the same proportions such that

length%2Fwidth=8%2F6=12%2Fw where w is the width of the enlarged picture

Step 2. Solving 8%2F6=12%2Fw

4%2F3=12%2Fw

Multiply by 3w/4 to both sides of the equation

%28w3%2F4%29%2A%284%2F3%29=%283w%2F4%29%2A%2812%2Fw%29

w=9

Step 3. ANSWER: The enlarged width is 9 inches.

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV


Travel_Word_Problems/227740: if a car averages 55 mph on a certain trip, it will arrive 2 hours early. If the car averages 35 mph it will arrive 2 hours late. How many miles is the trip?
1 solutions

Answer 169210 by drj(1380) About Me  on 2009-10-16 22:00:18 (Show Source):
You can put this solution on YOUR website!
If a car averages 55 mph on a certain trip, it will arrive 2 hours early. If the car averages 35 mph it will arrive 2 hours late. How many miles is the trip?

Step 1. distance = speed * time

Step 2. Let t be the time of the trip traveling on time.

Step 3. Let t-2 be the time if traveling at 55 mph.

Step 4. Let 55(t-2) be the distance traveling at 55 mph.

Step 5. Let 35(t+2) be the distance traveling at 35 mph.

Step 6. Then, 55(t-2)=35(t+2) since the distances are equal in Steps 4 and 5.

Step 7. Solving the equation in Step 6 yields the following steps

55t-110=35t%2B70

Add 110-35t to both sides of the equation

55t-110%2B110-35t=35t%2B70%2B110-35t

20t=180

Divide by 20 to both sides of the equation

20t%2F20=180%2F20

t=9

Substitute the value of t in Steps 4 or 5. We'll do both to check if distances are equal

55%289-2%29=385 miles and 35%289%2B2%29=385 miles.

Step 8. The distance is 385 miles.

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV


Linear_Equations_And_Systems_Word_Problems/227736: I need help solving this equation: 9a=-a%5E2-18
1 solutions

Answer 169204 by drj(1380) About Me  on 2009-10-16 21:46:19 (Show Source):
You can put this solution on YOUR website!
I need help solving this equation: 9a=-a%5E2-18

Step 1. Add a%5E2%2B18 to both sides of the equation.

9a%2Ba%5E2%2B18=-a%5E2-18%2Ba%5E2%2B18

a%5E2%2B9a%2B18=0 where we simplified and arranged in descending order.

Step 2. To solve, use the quadratic equation given as

x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

where a=1, b=9 and c=18.

Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B9x%2B18+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%289%29%5E2-4%2A1%2A18=9.

Discriminant d=9 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-9%2B-sqrt%28+9+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%289%29%2Bsqrt%28+9+%29%29%2F2%5C1+=+-3
x%5B2%5D+=+%28-%289%29-sqrt%28+9+%29%29%2F2%5C1+=+-6

Quadratic expression 1x%5E2%2B9x%2B18 can be factored:
1x%5E2%2B9x%2B18+=+1%28x--3%29%2A%28x--6%29
Again, the answer is: -3, -6. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B9%2Ax%2B18+%29



Step 3. ANSWER: The solutions are -3 and -6.

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV



Equations/227738: Can you help me solve the system?
x+2y=-12
y=20-2x
1 solutions

Answer 169200 by drj(1380) About Me  on 2009-10-16 21:42:09 (Show Source):
You can put this solution on YOUR website!
Can you help me solve the system?

x+2y=-12
y=20-2x or 2x+y=20

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++1%5Cx+%2B+2%5Cy+=+-12%2C%0D%0A++++2%5Cx+%2B+1%5Cy+=+20+%29%0D%0A++We'll use substitution. After moving 2*y to the right, we get:
1%2Ax+=+-12+-+2%2Ay, or x+=+-12%2F1+-+2%2Ay%2F1. Substitute that
into another equation:
2%2A%28-12%2F1+-+2%2Ay%2F1%29+%2B+1%5Cy+=+20 and simplify: Error: 'Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. '. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115.
error_location: 101



I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV



Equations/227739: I need help solving this equation
Solve the system
2x+5y=1
-x+6y=8
1 solutions

Answer 169198 by drj(1380) About Me  on 2009-10-16 21:40:16 (Show Source):
You can put this solution on YOUR website!
I need help solving this equation

Solve the system

2x+5y=1
-x+6y=8

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++2%5Cx+%2B+5%5Cy+=+1%2C%0D%0A++++-1%5Cx+%2B+6%5Cy+=+8+%29%0D%0A++We'll use substitution. After moving 5*y to the right, we get:
2%2Ax+=+1+-+5%2Ay, or x+=+1%2F2+-+5%2Ay%2F2. Substitute that
into another equation:
-1%2A%281%2F2+-+5%2Ay%2F2%29+%2B+6%5Cy+=+8 and simplify: Error: 'Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. '. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115.
error_location: 101



I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV


Equations/227730: Can someone pls show me how to solve this equation using the addition/elimination process?
1.8x-2y=0.9
0.04x+0.18y=0.15
1 solutions

Answer 169197 by drj(1380) About Me  on 2009-10-16 21:29:13 (Show Source):
You can put this solution on YOUR website!
Can someone pls show me how to solve this equation using the addition/elimination process?
1.8x-2y=0.9 Equation A
0.04x+0.18y=0.15 Equation B

Step 1. Multiply by 0.09 to Equation A to both sides of the equation

0.162x-0.18y=0.081 Equation A1
0.04x%2B0.18y=0.15 Equation B
Step 2. Add Equations A1 and B to eliminate the y terms.

0.162x%2B0.04x-0.18y%2B0.18y=0.081%2B0.15

0.202x=0.231

Step 3. Divide by 0.202 to both sides of the equation

0.202x%2F0.202=0.231%2F0.202

x=1.143

Step 4. Substitute x=1.143 into Equation A 1.8x-2y=0.9 to solve for y.

1.8%2A1.143-2y=0.9

2.0584-2y=0.9

Step 5. Add 2y-0.9 to both sides of the equation

2.0584-2y%2B2y-0.9=0.9%2B2y-0.9

1.1584=2y

Step 6. Divide by 2 to both sides of the equation

y=0.5792

Step 7. ANSWER: The solution is x=1.143 and y=0.5792

As a check, use the substitution shown below which have the same results.

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
We'll use substitution. After moving -2*y to the right, we get:
1.8%2Ax+=+0.9+-+-2%2Ay, or x+=+0.9%2F1.8+-+-2%2Ay%2F1.8. Substitute that
into another equation:
0.04%2A%280.9%2F1.8+-+-2%2Ay%2F1.8%29+%2B+0.18%5Cy+=+0.15 and simplify: Error: 'Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. '. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115.
error_location: 101


I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV






Coordinate-system/227726: When traveling to work each day, John drives part of it on the highway (where he goes 65 mph) and the rest on a ranch road (where he can only go 42 mph). The trip is 13.95 miles, and it takes only 15 minutes (which is 1/4 hour , or 0.25 hours). What part of an hour does he spend driving on each type of road?
1 solutions

Answer 169196 by drj(1380) About Me  on 2009-10-16 21:14:55 (Show Source):
You can put this solution on YOUR website!
When traveling to work each day, John drives part of it on the highway (where he goes 65 mph) and the rest on a ranch road (where he can only go 42 mph). The trip is 13.95 miles, and it takes only 15 minutes (which is 1/4 hour , or 0.25 hours). What part of an hour does he spend driving on each type of road?

Step 1. Let t be the time (in hours) traveled on the highway.

Step 2. Let 65t be the distance traveled on the highway.

Step 3. Let 0.25-t be the time traveled (in hours) on the ranch road.

Step 4. Let 42(.25-t) be the distance traveled on the ranch road.

Step 5. Then 13.95=65t+42(0.25-t)=10.5+23t since the total distance is 13.95 miles.

Step 6. Solving yields the following steps

13.95=10.5%2B23t

Subtract 10.5 from both sides of the equation

13.95-10.5=10.5%2B23t-10.5

3.45=23t

Divide by 23 to both sides of the equation

3.45%2F23=23t%2F23

t=0.15 hour and 0.25-t=0.10 hour

Check distance traveled 65*0.15+42*0.10=9.75+4.2=13.95 which is a true statement.

Step 7. ANSWER: John spent 0.15 hour on the highway and 0.10 hour on the ranch road.

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV


Linear-equations/227722: 7x+7y=28
-7x+y=57
Solve by the substitution method
1 solutions

Answer 169195 by drj(1380) About Me  on 2009-10-16 20:59:11 (Show Source):
You can put this solution on YOUR website!
7x+7y=28
-7x+y=57

Solve by the substitution method

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++7%5Cx+%2B+7%5Cy+=+28%2C%0D%0A++++-7%5Cx+%2B+1%5Cy+=+57+%29%0D%0A++We'll use substitution. After moving 7*y to the right, we get:
7%2Ax+=+28+-+7%2Ay, or x+=+28%2F7+-+7%2Ay%2F7. Substitute that
into another equation:
-7%2A%2828%2F7+-+7%2Ay%2F7%29+%2B+1%5Cy+=+57 and simplify: Error: 'Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. '. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115.
error_location: 101



I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV

Travel_Word_Problems/227725: An airplane flew with the wind for 5 hours. The return trip against the wind took 6 hours. If the wind was blowing at 25mph. What was the rate of the plane in still the air?
1 solutions

Answer 169194 by drj(1380) About Me  on 2009-10-16 20:56:54 (Show Source):
You can put this solution on YOUR website!
An airplane flew with the wind for 5 hours. The return trip against the wind took 6 hours. If the wind was blowing at 25mph. What was the rate of the plane in still the air?

Step 1. distance= speed * time

Step 2. Let x+25 be the airplane speed with the wind.

Step 3. Let x-25 be the airplane speed against the wind.

Step 4. Let 5(x+25) be the distance traveled with the wind after 5 hours.

Step 5. Let 6(x-25) be the distance traveled again the wind after 6 hours.

Step 6. Equate Steps 4 and 5 since the distances are the same.

5%28x%2B25%29=6%28x-25%29

5x%2B125=6x-150

Add 150-5x to both sides of the equation

5x%2B125%2B150-5x=6x-5x

275=x

Check if distances are equal: (275+25)5=(275-25)6 which is a true statement.

Step 7. ANSWER: The speed of the plane is 275 miles per hour.

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV




Travel_Word_Problems/227721: The speed of train A is 12 km/hr is slower than the speed of train B. Train A travels 230 km in the same time it takes train B to travel 290 km,. Find the speed of each.
1 solutions

Answer 169192 by drj(1380) About Me  on 2009-10-16 20:48:35 (Show Source):
You can put this solution on YOUR website!
The speed of train A is 12 km/hr is slower than the speed of train B. Train A travels 230 km in the same time it takes train B to travel 290 km,. Find the speed of each.

Step 1. distance=speed+%2A+time or time=distance%2Fspeed

Step 2. Let x be the speed of train B

Step 3. Let x-12 be the speed of train A since it is 12 km/hr slower.

Step 4. Let time=distance%2Fspeed=230%2F%28x-12%29 be the time traveled by train A.

Step 5. Let time=distance%2Fspeed=290%2Fx be the time traveled by train B.

Step 6. Set the equations in Steps 4 and 6 since they traveled at the same time.

230%2F%28x-12%29=290%2Fx

Multiply by x%28x-12%29 to both sides of the equation to get rid of the denominators.

x%28x-12%29%2A%28230%2F%28x-12%29%29=x%28x-12%29%2A%28290%2Fx%29

230x=290%28x-12%29

230x=290x-290%2A12

230x=290x-3480

Add 3480-230x to both sides of the equation


230x%2B3480-230x=290x-3480%2B34080-230x

3480=60x

Divide by 60 to both sides of the equation

3480%2F60=60x%2F60

x=58 speed of Train B and hours which is a true statement.

Step 7. ANSWER: The speed of Train A is 46 km/hr and speed of Train B is 58 km/hr.

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV


Linear-systems/227550: Why is it true that at x-intercept, the value of y is 0, and at y-intercept, the value of x is 0?
1 solutions

Answer 169183 by drj(1380) About Me  on 2009-10-16 19:59:49 (Show Source):
You can put this solution on YOUR website!
Why is it true that at x-intercept, the value of y is 0,
and at y-intercept, the value of x is 0?

To answer your question, let's look at an example
shown below by graphing two points since two points make a line:

2x%2B5y=10 Equation of a line in standard form.

Step 1. Let x=0 then 5y=10 or y=2. So one point is (0,2).

Step 2. Let y=0 then 2x=10 or x=5. So another point is (5,0).

Step 3. Now, draw a graph using these two points (0,2) and (5,0).

graph%28400%2C400%2C+-10%2C10%2C-10%2C10%2C+-2x%2F5%2B2%29

Step 4. Note that at point (0,2) the line intersects the y-axis and at point(5,0) the line intersects the x-axis.

So the y-intercept is when x=0 or at point (0,2).

And the x-intercept is when y=0 or at point (5,0).

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV


Linear_Equations_And_Systems_Word_Problems/227712: eight times a number plus six less than twice the number is 34
1 solutions

Answer 169180 by drj(1380) About Me  on 2009-10-16 19:50:34 (Show Source):
You can put this solution on YOUR website!
Eight times a number plus six less than twice the number is 34.

Step 1. Let n be the number.

Step 2. Let 8n be eight times a number

Step 3. Let 8n+2n-6 be eight times a number plus 6 less than twice the number

Step 4. Then 8n+2n-6=34 since eight times a number plus six less than twice the number is 34.

Step 5. Solving yields the following steps.

10n-6=34

Add 6 to both sides of the equation

10n-6%2B6=34%2B6

10n=40

Divide by 10 to both sides of the equation

10n%2F10=40%2F10

n=4

Step 6. ANSWER: The number is 4.

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV


Trigonometry-basics/227714: -6-4y=-24
2x+7y=13
1 solutions

Answer 169176 by drj(1380) About Me  on 2009-10-16 19:34:57 (Show Source):
You can put this solution on YOUR website!
-6-4y=-24 Equation A (see Step 8 if you meant -6x-4y=-24)
2x+7y=13 Equation B

Step 1. Solve for y in Equation A -6-4y=-24.

Step 2. Add 6 to both sides of the equation

-6-4y%2B6=-24%2B6

-4y=-18

Step 3. Divide by -4 to both sides of the equation

-4y%2F-4=-18%2F-4

y=18%2F4=9%2F2

Step 4. Now substitute y=9%2F2 into 2x%2B7y=13.

2x%2B7%2A%289%2F2%29=13

2x%2B63%2F2=26%2F2

Step 5. Subtract 63%2F2 from both sides of the equation

2x%2B63%2F2-63%2F2=26%2F2-63%2F2

2x=-37%2F2

Step 6. Divide by 2 to both sides of the equation

2x%2F2=-37%2F%282%2A2%29

x=-37%2F4

Step 7. ANSWER: x=-37%2F4 and y=9%2F2

Step 8. Now, I'll assume you meant to solve the following linear system of equations

-6x-4y=-24 Equation A
2x+7y=13 Equation B

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++-6%5Cx+%2B+-4%5Cy+=+-24%2C%0D%0A++++2%5Cx+%2B+7%5Cy+=+13+%29%0D%0A++We'll use substitution. After moving -4*y to the right, we get:
-6%2Ax+=+-24+-+-4%2Ay, or x+=+-24%2F-6+-+-4%2Ay%2F-6. Substitute that
into another equation:
2%2A%28-24%2F-6+-+-4%2Ay%2F-6%29+%2B+7%5Cy+=+13 and simplify: Error: 'Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. '. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115.
error_location: 101




I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV
















I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV

Equations/227711: How would you write the line x=4 in standard form ?
1 solutions

Answer 169169 by drj(1380) About Me  on 2009-10-16 19:20:16 (Show Source):
You can put this solution on YOUR website!
How would you write the line x=4 in standard form ?

Step 1. The given equation x=4 is already in standard form.

Step 2. The standard form is given as Ax+By=C where A, B, and C are constants.

Step 3. Then, for x=4 then A=1, B=0, and C=4.

Step 4. ANSWER: So in standard form we have 1x%2B0y=4 or simplifying x=4

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV



Travel_Word_Problems/227708: Two vehicles, a car and a truck. leave an intersection at the same time. The car heads east at an average speed of 60 miles per hour, while the truck heads south at an average speed of 20 miles per hour. Find an expression for their distance apart d in miles at the end of t hours.
1 solutions

Answer 169163 by drj(1380) About Me  on 2009-10-16 19:05:19 (Show Source):
You can put this solution on YOUR website!
Two vehicles, a car and a truck. leave an intersection at the same time. The car heads east at an average speed of 60 miles per hour, while the truck heads south at an average speed of 20 miles per hour. Find an expression for their distance apart d in miles at the end of t hours.

Step 1. distance= speed * time.

Step 2. Let 60t be the car traveling EAST at 60 miles per hour after t hours

Step 3. Let 20t be the distance of the truck traveling SOUTH at 20 miles per hour after t hours.

Step 4. Use the Pythagorean Theorem to find the distance d (hypotenuse) given as the sum of the squares of the legs (legs for our example given as 60t and 20t) is equal to the square of the hypotenuse d.

d%5E2=%2860t%29%5E2%2B%2820t%29%5E2

d%5E2=3600t%5E2%2B400t%5E2

d%5E2=4000t%5E2

Take the square root to both sides of the equation yields

d=t%2Asqrt%284000%29=63.24t

Step 5. ANSWER is d=t%2Asqrt%284000%29=63.24t


I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV