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Angles/222600: Find the measure of an angle if the measure of is complement is 53 degrees. Thank you for all the help and sorry if this has disturbed you in any way.
1 solutions

Answer 166652 by drj(1380) About Me  on 2009-10-06 17:00:47 (Show Source):
You can put this solution on YOUR website!
Find the measure of an angle if the measure of is complement is 53 degrees.

Step 1. Complementary angles means two angles add up to 90 degrees.

Step 2. Let x be the angle.

Step 3. Let 90-x be its complement.

Step 4. Given 90-x=53 or x=90-53=37.

Step 5. ANSWER: The angle is 37 degrees.

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.

Good luck in your studies!

Respectfully,
Dr J


Linear-systems/222598: Write the equation in the slope-intercept form and then find the slope m and y-intercept b of the corresponding line.
-8x + 6y - 5 = -7
1 solutions

Answer 166651 by drj(1380) About Me  on 2009-10-06 16:58:37 (Show Source):
You can put this solution on YOUR website!
Write the equation in the slope-intercept form and then find the slope m and y-intercept b of the corresponding line.
-8x + 6y - 5 = -7

Step 1. The slope-intercept form is y=mx+b where m is the slope and b is the y-intercept at x=0 or at point (0,b).

Step 2. Solving yields the following steps.

-8x%2B6y-5=-7

Add 8x+5 to both sides of the equation

-8x%2B6y-5%2B8x%2B5=-7%2B8x%2B5

6y=8x-2

Divide 6 to both sides of the equation

6y%2F6=8x%2F6-2%2F6

y=4x%2F3-1%2F3

Step 3. The slope m=4/3 and y-intercept b=-1/3}}}

Below is the graph and note the slope and y-intercept.

graph%28400%2C400%2C+-10%2C10%2C-10%2C10%2C+4x%2F3-1%2F3%29

I hope the above steps were helpful.

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Respectfully,
Dr J


Linear-equations/222591: y=2x-4
y=2x+4
1 solutions

Answer 166647 by drj(1380) About Me  on 2009-10-06 16:53:15 (Show Source):
You can put this solution on YOUR website!
y=2x-4 Equation A
y=2x+4 Equation B

Subtract Equation A from Equation B
y-y=2x-2x+4-(-4)

0=8 ...Not a true statement. We also note that the lines are parallel since they have the same slope m=2 since the above equations are in slope-intercept form y=mx+b where m is the slope and b is the y-intercept when x=0 or at point(0,b).

ANSWER: There is no solution since the two lines cannot intersect or are in parallel.

I hope the above steps were helpful.

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Respectfully,
Dr J


Linear-systems/222592: 5.7m+2.25=19.35
1 solutions

Answer 166643 by drj(1380) About Me  on 2009-10-06 16:47:37 (Show Source):
You can put this solution on YOUR website!
5.7m%2B2.25=19.35

Step 1. Subtract 2.25 from both sides of the equation

5.7m%2B2.25-2.25=19.35-2.25

5.7m=17.10

Step 2. Divide by 5.7 to both sides of the equation

5.7m%2F5.7=17.10%2F5.7

m=3

Step 3. ANSWER: The solution is m=3.

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.

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Respectfully,
Dr J


Age_Word_Problems/222583: Carl is twice as old as Rita. Meg is 5 years older than Carl. If the combined age is 155, how old is Meg?
1 solutions

Answer 166642 by drj(1380) About Me  on 2009-10-06 16:44:32 (Show Source):
You can put this solution on YOUR website!
Carl is twice as old as Rita. Meg is 5 years older than Carl. If the combined age is 155, how old is Meg?

Step 1. Let x be the age of Rita.

Step 2. Let 2x be the age of Carl since he is twice as old as Rita.

Step 3. Let 2x+5 since Meg is 5 years older than Carl.

Step 4. Then x+2x+2x+5=155 since their combined age is 155.

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

5x%2B5=155

Subtract 5 from both sides of the equation

5x%2B5-5=155-5

5x=150

Divide by 5 to both sides of the equation

5x%2F5=150%2F5

x=30, then 2x=60 and 2x%2B5=65. Note that the combined age is 155.

Step 6. ANSWER: The age of Meg is 65 years old. Note that Carl is 60 years old and Rita is 30 years old.

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.

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Respectfully,
Dr J





real-numbers/222567: between them, terry and shelly have 50 cassettes. if shelly has more than two thirds as many cassettes as terry, at least how many cassettes does shelly have? at most how much does terry have
1 solutions

Answer 166639 by drj(1380) About Me  on 2009-10-06 16:37:58 (Show Source):
You can put this solution on YOUR website!
Between them, Terry and Shelly have 50 cassettes. If Shelly has more than two thirds as many cassettes as Terry, at least how many cassettes does Shelly have? At most how much does Terry have?

Step 1. Let x be the number of cassettes Terry has.

Step 2. Let 2x%2F3 be the number of cassettes Shelly has since she has more than two-thirds as many cassettes as Terry.

Step 3. Then x%2B2x%2F3=5x%2F3=50 be the total of cassettes.

Step 4. Solving for x yields the following steps:

Multiply by 3%2F5 to both sides of the equation to find x

5x%2F3=50

3%2A5x%2F%285%2A3%29=3%2A50%2F5

x=30 and 2x%2F3=20 and both add up to 50 cassettes.

Step 5. ANSWER: Terry has 30 cassettes and Shelley has 20 cassettes.

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.

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Respectfully,
Dr J



Angles/222576: Angle A and angle B are complementary. The measure of angle B is 3 times the measure of A. Find the measure of angles A and B.
1 solutions

Answer 166631 by drj(1380) About Me  on 2009-10-06 16:25:14 (Show Source):
You can put this solution on YOUR website!
Angle A and angle B are complementary. The measure of angle B is 3 times the measure of A. Find the measure of angles A and B.

Step 1. Complementary angles means two angles add up to 90 degrees.

Step 2. Let A be one angle.

Step 3. Let B=90-A be its complement.

Step 4. B=3A or 90-A=3A since the measure of B is 3 time the measure of A.

Step 5. Solving yields the following steps

90-A=3A

Add A to both sides of the equation

90-A%2BA=3A%2BA

90=4A

Divide 4 to both sides of the equation

90%2F4=4A%2F4

22.5=A Then B=3A=67.5

Step 6. ANSWER: The complementary angles are A=22.5 and B=67.5 degrees.

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.

Good luck in your studies!

Respectfully,
Dr J


Exponents/222566: How do you write the number 1,203,487,386 in expanded form using exponets?
1 solutions

Answer 166625 by drj(1380) About Me  on 2009-10-06 16:19:23 (Show Source):
You can put this solution on YOUR website!
How do you write the number 1,203,487,386 in expanded form using exponents?



I hope the above steps were helpful.

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Good luck in your studies!

Respectfully,
Dr J


Numbers_Word_Problems/222515: If jay and isabella have 59 movies together and jay has 13 more than isabella how many movies do each of them have
1 solutions

Answer 166591 by drj(1380) About Me  on 2009-10-06 15:06:19 (Show Source):
You can put this solution on YOUR website!
If Jay and Isabella have 59 movies together and jay has 13 more than Isabella how many movies do each of them have

Step 1. Let x be the number of movies Isabella has.

Step 2. Let x+13 be the number of movies Jay has.

Step 3. Then, x+x+13=59 since they both have 59 movies.

Step 4. Solving yields the following steps

2x%2B13=59

Subtract 13 from both sides of the equation

2x%2B13-13=59-13

2x=46

Divide 2 to both sides of the equation

2x%2F2=46%2F2

x=23 and x%2B13=36 and note total is 59.

Step 5. ANSWER: Jay has 36 movies and Isabella has 23 movies.

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.

Good luck in your studies!

Respectfully,
Dr J


Probability-and-statistics/222511: find the 50th term in the arithmetic sequence 1,5,9,....
1 solutions

Answer 166588 by drj(1380) About Me  on 2009-10-06 14:56:32 (Show Source):
You can put this solution on YOUR website!
Find the 50th term in the arithmetic sequence 1,5,9,....

Step 1. The constant for this sequence is 4 since 5-1=4 and 9-5=4.

Step 2. Using this constant, we have 1+(n-1)*4 as the formula. We can check with n=1 or 1+(1-1)*4=1. With n=2, 1+(2-1)*4=5. With n=3, 1+(3-1)4=9. So it checks out.

Step 3. With n=50, then 1+(50-1)*4=197.

Step 4. ANSWER: The 50th term is 197.

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.

Good luck in your studies!

Respectfully,
Dr J


Numbers_Word_Problems/222441: find three consecutive whole numbers such that twice the sum of the two smallest numbers is 10 more than three times the largest number
1 solutions

Answer 166587 by drj(1380) About Me  on 2009-10-06 14:52:10 (Show Source):
You can put this solution on YOUR website!
Find three consecutive whole numbers such that twice the sum of the two smallest numbers is 10 more than three times the largest number.

Step 1. Let n be an integer.

Step 2. Let n+1 and n+2 be the next two consecutive integers.

Step 3. Let n+n+1=2n+1 be the sum of the two smallest integers.

Step 4. Let 2(2n+1) be twice the sum of the two smallest integers.

Step 5. Let 3(n+2) be three times the largest number

Step 6. Then using Steps 3 and 4, 2(2n+1)=3(n+2)+10 since twice the sum of the two smallest numbers is 10 more than three times the largest number.

Step 7. 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: n=14.
  • Graphical form: Equation 2%2A%282n%2B1%29=3%2A%28n%2B2%29%2B10 was fully solved.
  • Text form: 2*(2n+1)=3*(n+2)+10 simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+2%2A%282n%2B1%29=3%2A%28n%2B2%29%2B10+%29
    For tutors: simplify_cartoon( 2*(2n+1)=3*(n+2)+10 )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at 2%2A%282%2An%2B1%29=highlight_red%28+3%2A%28n%2B2%29%2B10+%29.
Moved these terms to the left highlight_green%28+-3%2A%28n%2B2%29+%29,highlight_green%28+-10+%29
It becomes 2%2A%282%2An%2B1%29-highlight_green%28+3%2A%28n%2B2%29+%29-highlight_green%28+10+%29=0.

Look at highlight_red%28+2%2A%282%2An%2B1%29+%29-3%2A%28n%2B2%29-10=0.
Expanded term 2 by using associative property on %282%2An%2B1%29
It becomes highlight_green%28+2%2A2%2An+%29%2Bhighlight_green%28+2%2A1+%29-3%2A%28n%2B2%29-10=0.

Look at highlight_red%28+2+%29%2Ahighlight_red%28+2+%29%2An%2B2%2A1-3%2A%28n%2B2%29-10=0.
Multiplied numerator integers
It becomes highlight_green%28+4+%29%2An%2B2%2A1-3%2A%28n%2B2%29-10=0.

Look at 4%2An%2Bhighlight_red%28+2+%29%2Ahighlight_red%28+1+%29-3%2A%28n%2B2%29-10=0.
Multiplied numerator integers
It becomes 4%2An%2Bhighlight_green%28+2+%29-3%2A%28n%2B2%29-10=0.

Look at 4%2An%2Bhighlight_red%28+2+%29-3%2A%28n%2B2%29-highlight_red%28+10+%29=0.
Added fractions or integers together
It becomes 4%2An%2Bhighlight_green%28+-8+%29-3%2A%28n%2B2%29=0.

Look at 4%2An%2Bhighlight_red%28+-8+%29-3%2A%28n%2B2%29=0.
Moved -8 to the right of expression
It becomes 4%2An-3%2A%28n%2B2%29%2Bhighlight_green%28+-8+%29=0.

Look at 4%2An-3%2A%28n%2B2%29%2Bhighlight_red%28+-8+%29=0.
Removed extra sign in front of -8
It becomes 4%2An-3%2A%28n%2B2%29-highlight_green%28+8+%29=0.

Look at 4%2An-highlight_red%28+3%2A%28n%2B2%29+%29-8=0.
Expanded term -3 by using associative property on %28n%2B2%29
It becomes 4%2An-highlight_green%28+3%2An+%29-highlight_green%28+3%2A2+%29-8=0.

Look at 4%2An-3%2An-highlight_red%28+3+%29%2Ahighlight_red%28+2+%29-8=0.
Multiplied numerator integers
It becomes 4%2An-3%2An-highlight_green%28+6+%29-8=0.

Look at 4%2An-3%2An-highlight_red%28+6+%29-highlight_red%28+8+%29=0.
Added fractions or integers together
It becomes 4%2An-3%2An%2Bhighlight_green%28+-14+%29=0.

Look at 4%2An-3%2An%2Bhighlight_red%28+-14+%29=0.
Removed extra sign in front of -14
It becomes 4%2An-3%2An-highlight_green%28+14+%29=0.

Look at highlight_red%28+4%2An+%29-highlight_red%28+3%2An+%29-14=0.
Eliminated similar terms highlight_red%28+4%2An+%29,highlight_red%28+-3%2An+%29 replacing them with highlight_green%28+%284-3%29%2An+%29
It becomes highlight_green%28+%284-3%29%2An+%29-14=0.

Look at highlight_red%28+%284-3%29+%29%2An-14=0.
Remove extraneous '1' from product highlight_red%28+%284-3%29+%29
It becomes n-14=0.

Look at highlight_red%28+n-14+%29=0.
Solved linear equation highlight_red%28+n-14=0+%29 equivalent to n-14 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: n=14.

Universal Simplifier and Solver


Done!



n=14, then n+1=15 and n+2=16

Check original equation 2%282n%2B1%29=3%28n%2B2%29%2B10 or 2%2814%2B15%29=3%2A16%2B10 such that 58=58 which is a true statement.

Step 8. ANSWER: The three consecutive integers are 14, 15, and 16.

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.

Good luck in your studies!

Respectfully,
Dr J


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.

Good luck in your studies!

Respectfully,
Dr J


Geometry_Word_Problems/222404: two planes leave an airport at the same time and fly in opposite directions. one of the planes is flying at 450 mph, and the other is flying 550 mph. in how many hours will they be 2,000 miles apart?
1 solutions

Answer 166584 by drj(1380) About Me  on 2009-10-06 14:42:00 (Show Source):
You can put this solution on YOUR website!
Two planes leave an airport at the same time and fly in opposite directions. One of the planes is flying at 450 mph, and the other is flying 550 mph. In how many hours will they be 2,000 miles apart?

Step 1. time = distance/speed or distance=speed*time

Step 2. Let x be the number of hours that the two planes will be 2000 miles apart.

Step 3. Let 450x be the distance traveled by the plane at 450 mph.

Step 4. Let 550x be the distance traveled by the plane at 500 mph.


Step 5. 450x+550x=2000 be the total distance traveled by both planes.

Step 6. Solving yields the following steps.

1000x=2000

Divide 1000 to both sides of the equation

1000x%2F1000=2000%2F1000

x=2

Check... 2*(550+450)=2000...which is a true statement.

Step 7. ANSWER: The time will take 2 hours when they are 2000 miles apart.

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.

Good luck in your studies!

Respectfully,
Dr J




Expressions-with-variables/222382: Solve by the substitution method.
6x+7y=-29
x=3-9y
What is the solution of the system? Type an ordered pair.
1 solutions

Answer 166582 by drj(1380) About Me  on 2009-10-06 14:33:59 (Show Source):
You can put this solution on YOUR website!
Solve by the substitution method.

6x+7y=-29
x=3-9y or x+9y=3 after adding 9y to both sides of the equation.

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++6%5Cx+%2B+7%5Cy+=+-29%2C%0D%0A++++1%5Cx+%2B+9%5Cy+=+3+%29%0D%0A++We'll use substitution. After moving 7*y to the right, we get:
6%2Ax+=+-29+-+7%2Ay, or x+=+-29%2F6+-+7%2Ay%2F6. Substitute that
into another equation:
1%2A%28-29%2F6+-+7%2Ay%2F6%29+%2B+9%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.

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Good luck in your studies!

Respectfully,
Dr J



expressions/222486: X=6, y=-4, a=3
6x - 5y + 4a
evaluate.
1 solutions

Answer 166580 by drj(1380) About Me  on 2009-10-06 14:30:23 (Show Source):
You can put this solution on YOUR website!
x=6, y=-4, a=3

6x - 5y + 4a

Evaluate.

6x-5y%2B4a=6%2A6-5%2A%28-4%29%2B4%2A3=36%2B20%2B12=68

ANSWER: 6x+-+5y+%2B+4a=68

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.

Good luck in your studies!

Respectfully,
Dr J


percentage/222481: Amy paid $80.83 for a pair of running shoes during a 15% off sale. What was the regular price?
1 solutions

Answer 166578 by drj(1380) About Me  on 2009-10-06 14:27:15 (Show Source):
You can put this solution on YOUR website!
Amy paid $80.83 for a pair of running shoes during a 15% off sale. What was the regular price?

Step 1. 15% means 0.15.

Step 2. Let x be the original price.

Step 3. Let x-0.15x be dollar value that is 15% off.

Step 4. Then 80.83=x-0.15x since Amy paid $80.83 for a pair of running shoes during a 15% off sale/

Step 5. Solving yields the following steps

80.83=0.85x

Dividing 0.85 to both sides of the equation yields

80.83%2F0.85=085x%2F0.85

x=95.09

Step 6. ANSWER: The regular price is $95.09.

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.

Good luck in your studies!

Respectfully,
Dr J


Linear-equations/222470: Show the graph y=-5x
1 solutions

Answer 166575 by drj(1380) About Me  on 2009-10-06 14:21:07 (Show Source):
You can put this solution on YOUR website!
Show the graph y=-5x

Step 1. Two points are required to make a line. Try x=0, then y=-5*0=0 so one point is (0,0). Letting x=1, then y=-5*1=-5 and we have another point (1,-5).


Step 2. Graph is shown below.

graph%28500%2C500%2C+-15%2C+15%2C+-15%2C+15%2C+-5x%29

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.

Good luck in your studies!

Respectfully,
Dr J


Complex_Numbers/222474: a/4+5=5/2

1 solutions

Answer 166572 by drj(1380) About Me  on 2009-10-06 14:17:37 (Show Source):
You can put this solution on YOUR website!
a%2F4%2B5=5%2F2

Step 1. Multiply by 4 to both sides of the equation

4%2Aa%2F4%2B4%2A5=4%2A5%2F2

a%2B20=10

Step 2. Subtract 20 from both sides of the equation

a%2B20-20=10-20

a=-10

Check original equation...a%2F4%2B5=-10%2F4%2B5=5%2F2...which is a true statement.

Step 3. ANSWER: a=-10


Quadratic_Equations/222390: how do i solve by factoring, x squared-13x+40=0
1 solutions

Answer 166568 by drj(1380) About Me  on 2009-10-06 14:13:52 (Show Source):
You can put this solution on YOUR website!
How do i solve by factoring,x%5E2-13x%2B40=0

Step 1. Find two integers m and n whose sum m%2Bn=-13 and whose product is mn=40

Step 2. After trial and error, the integers are m=-5 and n=-8.

Step 3. Then using these integers we have x%5E2-13x%2B40=%28x-5%29%28x-8%29=0

Step 4. We have two solutions, x-5=0 and x-8=0 or x=5 and x=8.

Step 5. ANSWER: The answer is x=5 and x=8.

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.

Good luck in your studies!

Respectfully,
Dr J


Complex_Numbers/222460: x/3-1/2=5/6

1 solutions

Answer 166565 by drj(1380) About Me  on 2009-10-06 14:06:38 (Show Source):
You can put this solution on YOUR website!
x%2F3-1%2F2=5%2F6

Step 1. Multiply 6 to both sides of the equation to get rid of denominators.

6%2Ax%2F3-6%2A1%2F2=6%2A5%2F6

2x-3=5

Step 2. Add 3 from to both sides of the equation

2x-3%2B3=5%2B3

2x=8

Step 3. Divide by 2 to both sides of the equation

2x%2F2=8%2F2

x=4

Check with original equation...x%2F3-1%2F2=4%2F3-1%2F2=8%2F6-3%2F6=5%2F6... which is a true statement.

Step 4. ANSWER: 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.

Good luck in your studies!

Respectfully,
Dr J


absolute-value/221656: Hi, I have an absolute value problem. I tried solving it like a regular equation, but when I check it it is wrong. The problem is 6|5x+45|-113=7.
Thanks in advance.
1 solutions

Answer 166208 by drj(1380) About Me  on 2009-10-04 21:19:46 (Show Source):
You can put this solution on YOUR website!
Hi, I have an absolute value problem. I tried solving it like a regular equation, but when I check it it is wrong. The problem is 6|5x+45|-113=7.
Thanks in advance.

Step 1. Note that abs%285x%2B45%29 is the same as 5x+45 when 5x+45 is positive and -(5x+45) when 5x+45 is negative.

Step 2. Let z=abs%285x%2B45%29

6z-113=7

Add 113 to both sides

6z-113%2B113=7%2B113

6z=120

Divide 6 to both sides of the equation

6z%2F6=120%2F6

z=20

20=5x%2B45 and 20=-%285x%2B45%29 or -20=5x%2B45

-25=5x and -65=5x

x=-5 and x=-13

Step 3. ANSWER is x=-5 and x=-13.

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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Angles/221642: the measure of the supplement of an angle exceeds three times the measure of the compliment by 30.
1 solutions

Answer 166199 by drj(1380) About Me  on 2009-10-04 21:06:51 (Show Source):
You can put this solution on YOUR website!
The measure of the supplement of an angle exceeds three times the measure of the complement by 30.

Step 1. Supplementary angles means two angles add up to 180 degrees.

Step 2. Complementary angles means two angles add up to 90 degrees.

Step 3. Let x be the angle.

Step 4. Let 180-x be its supplementary angle.

Step 5. Let 90-x be its complementary angle.

Step 6. Let 3(90-x) be three times the complement.

Step 7. Then 180-x=3(90-x)+30 since the measure of the supplement of an angle exceeds three times the measure of the complement by 30.

Step 8. Solving the equation in Step 7 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: x=60.
  • Graphical form: Equation 180-x=3%2A%2890-x%29%2B30 was fully solved.
  • Text form: 180-x=3*(90-x)+30 simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+180-x=3%2A%2890-x%29%2B30+%29
    For tutors: simplify_cartoon( 180-x=3*(90-x)+30 )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at highlight_red%28+180+%29-x=3%2A%2890-x%29%2B30.
Moved 180 to the right of expression
It becomes -x%2Bhighlight_green%28+180+%29=3%2A%2890-x%29%2B30.

Look at -x%2B180=3%2A%28highlight_red%28+90+%29-x%29%2B30.
Moved 90 to the right of expression
It becomes -x%2B180=3%2A%28-x%2Bhighlight_green%28+90+%29%29%2B30.

Look at -x%2B180=highlight_red%28+3%2A%28-x%2B90%29%2B30+%29.
Moved these terms to the left highlight_green%28+-3%2A%28-x%2B90%29+%29,highlight_green%28+-30+%29
It becomes -x%2B180-highlight_green%28+3%2A%28-x%2B90%29+%29-highlight_green%28+30+%29=0.

Look at -x%2Bhighlight_red%28+180+%29-3%2A%28-x%2B90%29-highlight_red%28+30+%29=0.
Added fractions or integers together
It becomes -x%2Bhighlight_green%28+150+%29-3%2A%28-x%2B90%29=0.

Look at -x%2Bhighlight_red%28+150+%29-3%2A%28-x%2B90%29=0.
Moved 150 to the right of expression
It becomes -x-3%2A%28-x%2B90%29%2Bhighlight_green%28+150+%29=0.

Look at -x-highlight_red%28+3%2A%28-x%2B90%29+%29%2B150=0.
Expanded term -3 by using associative property on %28-x%2B90%29
It becomes -x%2Bhighlight_green%28+3%2Ax+%29-highlight_green%28+3%2A90+%29%2B150=0.

Look at -x%2B3%2Ax-highlight_red%28+3+%29%2Ahighlight_red%28+90+%29%2B150=0.
Multiplied numerator integers
It becomes -x%2B3%2Ax-highlight_green%28+270+%29%2B150=0.

Look at -x%2B3%2Ax-highlight_red%28+270+%29%2Bhighlight_red%28+150+%29=0.
Added fractions or integers together
It becomes -x%2B3%2Ax%2Bhighlight_green%28+-120+%29=0.

Look at -x%2B3%2Ax%2Bhighlight_red%28+-120+%29=0.
Removed extra sign in front of -120
It becomes -x%2B3%2Ax-highlight_green%28+120+%29=0.

Look at -highlight_red%28+x+%29%2Bhighlight_red%28+3%2Ax+%29-120=0.
Eliminated similar terms highlight_red%28+-x+%29,highlight_red%28+3%2Ax+%29 replacing them with highlight_green%28+%28-1%2B3%29%2Ax+%29
It becomes highlight_green%28+%28-1%2B3%29%2Ax+%29-120=0.

Look at %28-highlight_red%28+1+%29%2Bhighlight_red%28+3+%29%29%2Ax-120=0.
Added fractions or integers together
It becomes %28highlight_green%28+2+%29%29%2Ax-120=0.

Look at highlight_red%28+%28highlight_red%28+2+%29%29%2Ax+%29-120=0.
Remove unneeded parentheses around factor highlight_red%28+2+%29
It becomes highlight_green%28+2+%29%2Ax-120=0.

Look at highlight_red%28+2%2Ax-120+%29=0.
Solved linear equation highlight_red%28+2%2Ax-120=0+%29 equivalent to 2*x-120 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: x=60.

Universal Simplifier and Solver


Done!



With x=60, then 180-x=120 and 90-x=30.

Check equation 180-x=3(90-x)+30 of Step 7 or 120=3*30+30=120 which is a true statement

Step 9. ANSWER: The angle is 60, its supplement is 120 and its complement is 30.


I hope the above steps were helpful.

For free Step-By-Step Videos on Intrduction 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


Linear-equations/221640: how do you solve for x and check the solution to the equation,

-0.3 + x-5(x + 1/10)= -0.8 + 5(-x+0.1)
1 solutions

Answer 166193 by drj(1380) About Me  on 2009-10-04 20:53:14 (Show Source):
You can put this solution on YOUR website!
How do you solve for x and check the solution to the equation,

-0.3+%2B+x-5%28x+%2B+1%2F10%29=+-0.8+%2B+5%28-x%2B0.1%29

Step 1. Multiply by 10 to both sides of the equation to get rid of the decimal point and denominator

-3%2B10x-50x-5%29=-8-50x%2B5

Step 2. Simplify as follows:

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


YOUR ANSWER


  • Here's what you tried:
  • This is an equation! Solutions: x=0.5.
  • Graphical form: Equation -3%2B10x-50x-5=-8-50x%2B5 was fully solved.
  • Text form: -3+10x-50x-5=-8-50x+5 simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+-3%2B10x-50x-5=-8-50x%2B5+%29
    For tutors: simplify_cartoon( -3+10x-50x-5=-8-50x+5 )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at -highlight_red%28+3+%29%2B10%2Ax-50%2Ax-highlight_red%28+5+%29=-8-50x%2B5.
Added fractions or integers together
It becomes highlight_green%28+-8+%29%2B10%2Ax-50%2Ax=-8-50x%2B5.

Look at highlight_red%28+-8+%29%2B10%2Ax-50%2Ax=-8-50x%2B5.
Moved -8 to the right of expression
It becomes 10%2Ax-50%2Ax%2Bhighlight_green%28+-8+%29=-8-50x%2B5.

Look at 10%2Ax-50%2Ax%2Bhighlight_red%28+-8+%29=-8-50x%2B5.
Removed extra sign in front of -8
It becomes 10%2Ax-50%2Ax-highlight_green%28+8+%29=-8-50x%2B5.

Look at highlight_red%28+10%2Ax+%29-highlight_red%28+50%2Ax+%29-8=-8-50x%2B5.
Eliminated similar terms highlight_red%28+10%2Ax+%29,highlight_red%28+-50%2Ax+%29 replacing them with highlight_green%28+%2810-50%29%2Ax+%29
It becomes highlight_green%28+%2810-50%29%2Ax+%29-8=-8-50x%2B5.

Look at %28highlight_red%28+10+%29-highlight_red%28+50+%29%29%2Ax-8=-8-50x%2B5.
Added fractions or integers together
It becomes %28highlight_green%28+-40+%29%29%2Ax-8=-8-50x%2B5.

Look at %28highlight_red%28+-40+%29%29%2Ax-8=-8-50x%2B5.
Removed extra sign in front of -40
It becomes %28-highlight_green%28+40+%29%29%2Ax-8=-8-50x%2B5.

Look at highlight_red%28+%28-highlight_red%28+40+%29%29%2Ax+%29-8=-8-50x%2B5.
Remove unneeded parentheses around factor highlight_red%28+40+%29
It becomes -highlight_green%28+40+%29%2Ax-8=-8-50x%2B5.

Look at -40%2Ax-8=-highlight_red%28+8+%29-50%2Ax%2Bhighlight_red%28+5+%29.
Added fractions or integers together
It becomes -40%2Ax-8=highlight_green%28+-3+%29-50%2Ax.

Look at -40%2Ax-8=highlight_red%28+-3+%29-50%2Ax.
Moved -3 to the right of expression
It becomes -40%2Ax-8=-50%2Ax%2Bhighlight_green%28+-3+%29.

Look at -40%2Ax-8=-50%2Ax%2Bhighlight_red%28+-3+%29.
Removed extra sign in front of -3
It becomes -40%2Ax-8=-50%2Ax-highlight_green%28+3+%29.

Look at -40%2Ax-8=highlight_red%28+-50%2Ax-3+%29.
Moved these terms to the left highlight_green%28+50%2Ax+%29,highlight_green%28+3+%29
It becomes -40%2Ax-8%2Bhighlight_green%28+50%2Ax+%29%2Bhighlight_green%28+3+%29=0.

Look at -40%2Ax-highlight_red%28+8+%29%2B50%2Ax%2Bhighlight_red%28+3+%29=0.
Added fractions or integers together
It becomes -40%2Ax%2Bhighlight_green%28+-5+%29%2B50%2Ax=0.

Look at -40%2Ax%2Bhighlight_red%28+-5+%29%2B50%2Ax=0.
Moved -5 to the right of expression
It becomes -40%2Ax%2B50%2Ax%2Bhighlight_green%28+-5+%29=0.

Look at -40%2Ax%2B50%2Ax%2Bhighlight_red%28+-5+%29=0.
Removed extra sign in front of -5
It becomes -40%2Ax%2B50%2Ax-highlight_green%28+5+%29=0.

Look at -highlight_red%28+40%2Ax+%29%2Bhighlight_red%28+50%2Ax+%29-5=0.
Eliminated similar terms highlight_red%28+-40%2Ax+%29,highlight_red%28+50%2Ax+%29 replacing them with highlight_green%28+%28-40%2B50%29%2Ax+%29
It becomes highlight_green%28+%28-40%2B50%29%2Ax+%29-5=0.

Look at %28-highlight_red%28+40+%29%2Bhighlight_red%28+50+%29%29%2Ax-5=0.
Added fractions or integers together
It becomes %28highlight_green%28+10+%29%29%2Ax-5=0.

Look at highlight_red%28+%28highlight_red%28+10+%29%29%2Ax+%29-5=0.
Remove unneeded parentheses around factor highlight_red%28+10+%29
It becomes highlight_green%28+10+%29%2Ax-5=0.

Look at highlight_red%28+10%2Ax-5+%29=0.
Solved linear equation highlight_red%28+10%2Ax-5=0+%29 equivalent to 10*x-5 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: x=0.5.

Universal Simplifier and Solver


Done!



Step 3. Check x=0.5 and substitute into original equation to see if you get a true statement.

-0.3+%2B+x-5%28x+%2B+1%2F10%29=+-0.8+%2B+5%28-x%2B0.1%29

-0.3%2B0.5-5%280.5%2B0.1%29=-0.8%2B5%28-0.5%2B0.1%29

-0.8%2B2-5%28-0.6%29=-0.8%2B%282.5%2B5%29

-0.8%2B3=-0.8%2B3

2.2=2.2 a true statement.

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





Sequences-and-series/221632: "write and solve an equation to find the nth term of each aritmetic sequence"
3,7,11,15, . . . n=8
10,5,0,-5, . . . n=21
34,49,64,79, . . . n=200

1 solutions

Answer 166186 by drj(1380) About Me  on 2009-10-04 20:41:50 (Show Source):
You can put this solution on YOUR website!
"Write and solve an equation to find the nth term of each arithmetic sequence"

Find the pattern or constant a to get the next term. So that

n0%2B%28n-1%29a

where a is a constant, n0 is the first term and n is the nth term.

We need (n-1) so when n=1 then n0 is the first term.

Step 1. 3,7,11,15, . . . n=8 3+(n-1)4=3+4n-4=4n-1.

ANSWER: 4n-1, at n=8 then 4*8-1=31

Step 2. 10,5,0,-5, . . . n=21 10-(n-1)5=10-5n-5=5-5n=5(1-n)

ANSWER: 5(1-n), at n=21 then 5(1-21)=100

Step 3. 34,49,64,79, . . . n=200 34+(n-1)15=34+15n-15=15n+19

ANSWER: 15n+19, at n=200 then 15*200+19=3000+19=3019.

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










Word_Problems_With_Coins/221577: Donnie has $5.10 in nickels, dimes, and quarters. He has an equal number of dimes and nickels, with the value of the quarters being $2.40 more than the total value of the dimes and nickels. How many dimes does he have?
1 solutions

Answer 166163 by drj(1380) About Me  on 2009-10-04 19:52:56 (Show Source):
You can put this solution on YOUR website!
Donnie has $5.10 in nickels, dimes, and quarters. He has an equal number of dimes and nickels, with the value of the quarters being $2.40 more than the total value of the dimes and nickels. How many dimes does he have?

Step 1. Let x be the number of nickels

Step 2. Let x be the number of dimes since they are equal in number with the nickels.

Step 3. Let %280.05%2B0.10%29x=0.15x be the dollar values of nickels and dimes.

Step 4. Let 0.25y be the dollar values of quarters.

Step 5. 2.40%2B0.15x=0.25y since the value of the quarters being $2.40 more than the total value of the dimes and nickels. Or rewriting it as

-0.15x%2B0.25y=2.40

Step 6. Also, 0.15x%2B0.25y=5.10 as given by the problem since $5.10 in nickels, dimes, and quarters.

Step 7. Now, we have a linear system of equations in Steps 5 and 6

-0.15x%2B0.25y=2.40 Equation A
0.15x%2B0.25y=5.10 Equation B

Adding Equations A and B

-0.15x%2B0.15x%2B0.25y%2B0.25y=2.40%2B5.10

0.50y=7.50

y=15 quarters

Then solving x from Equation B is 5.10-3.75=0.15x or x=9.

Check Equation A if true -0.15x%2B0.25y=2.40 or -1.35%2B3.75=2.40...which is a true statement.

Step 8. ANSWER: The number of nickels and dimes is 9 each and the number of quarters is 15.

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.

Good luck in your studies!

Respectfully,
Dr J













Graphs/221588: What is the slope and y-intercept of y = -2/3 x -12
1 solutions

Answer 166160 by drj(1380) About Me  on 2009-10-04 19:35:22 (Show Source):
You can put this solution on YOUR website!
What is the slope and y-intercept of y = -2/3 x -12

Step 1. The slope-intercept form is given at y=mx+b where m is the slope and b is the y-intercept when x=0 or at point (0,b).

Step 2. Given y=-2x%2F3-12 has a slope m=-2%2F3 and y-intercept at b=-12

Here's a graph of the above equation

graph%28+600%2C+600%2C+-20%2C+5%2C+-15%2C+5%2C+-2x%2F3-12%29

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.

Good luck in your studies!

Respectfully,
Dr J


Word_Problems_With_Coins/221578: Jay's favorite book is 182 pages less than three times Mitchel's favorite book. If both books have the same number of pages, how many pages are in Jay's favorite book?
1 solutions

Answer 166158 by drj(1380) About Me  on 2009-10-04 19:30:20 (Show Source):
You can put this solution on YOUR website!
Jay's favorite book is 182 pages less than three times Mitchel's favorite book. If both books have the same number of pages, how many pages are in Jay's favorite book?

Step 1. Let x be the number of pages in Mitchel's book.

Step 2. Let 3x be three times the number of pages in Mitchel's book

Step 3. Let 3x-182 be the number of pages in Jay's book since it's 182 pages less than three times Mitchel's favorite book

Step 4. Then, x=3x-182 since both books have the same number of pages

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

Add 182-x to both sides of the equation

x%2B182-x=3x-182%2B182-x

182=3x-x

+182=2x

Divide 2 to both sides of the equation

182%2F2=2x%2F2

x=91

The number of pages in Jay's book is 3x-182=3*91-182=91

Step 6. The number of pages in Jay's book is 91 pages.

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.

Good luck in your studies!

Respectfully,
Dr J


Rectangles/221566: the width of a rectangle is 5ft less than the length. the area is 6ft^2

1 solutions

Answer 166150 by drj(1380) About Me  on 2009-10-04 19:17:06 (Show Source):
You can put this solution on YOUR website!
The width of a rectangle is 5 ft less than the length. The area is 6ft^2

I assume you want to find the dimensions of the rectangle.

Step 1. Let L be the length.

Step 2. Let L-5 be the width.

Step 3. Area A=L%28L-5%29=6

Step 4. Solving A in Step 3 yields the following steps.

L%5E2-5L=6

Subtract 6 from both sides to get a quadratic equation

L%5E2-5L-6=6-6

L%5E2-5L-6=0

Step 5. To solve equation in Step 5, use the quadratic formula given below

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

where a=1, b=-5, and c=-6

Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation aL%5E2%2BbL%2Bc=0 (in our case 1L%5E2%2B-5L%2B-6+=+0) has the following solutons:

L%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=%28-5%29%5E2-4%2A1%2A-6=49.

Discriminant d=49 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--5%2B-sqrt%28+49+%29%29%2F2%5Ca.

L%5B1%5D+=+%28-%28-5%29%2Bsqrt%28+49+%29%29%2F2%5C1+=+6
L%5B2%5D+=+%28-%28-5%29-sqrt%28+49+%29%29%2F2%5C1+=+-1

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



Using the positive solution L=6, then L-5=1. Area A=6*1=6 which is a true statement.

Step 6. ANSWER: The dimensions of a rectangle are 6 feet and 1 feet.

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.

Good luck in your studies!

Respectfully,
Dr J





Rectangles/221567: the length of a rectangle is 12 meters longer than half the width. the area of the rectangle is 90 square meters. find the dimensions of the rectangle.
1 solutions

Answer 166147 by drj(1380) About Me  on 2009-10-04 19:08:36 (Show Source):
You can put this solution on YOUR website!
The length of a rectangle is 12 meters longer than half the width. The area of the rectangle is 90 square meters. Find the dimensions of the rectangle.

Step 1. Let w be the width.

Step 2. Let w%2F2%2B12 be the length.

Step 3. Area A=w%28w%2F2%2B12%29=90

Step 4. Solving A in Step 3 yields the following steps.

w%5E2%2F2+%2B12w=90

Multiply 2 to both sides to get rid of denominator

2w%5E2%2F2%2B2%2A12w=90%2A2

w%5E2%2B24w=180

Subtract 180 from both sides to get a quadratic equation

w%5E2%2B24w-180=180-180

w%5E2%2B24w-180=0

Step 5. To solve equation in Step 5, use the quadratic formula given below

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

where a=1, b=24, and c=-180

Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation aw%5E2%2Bbw%2Bc=0 (in our case 1w%5E2%2B24w%2B-180+=+0) has the following solutons:

w%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=%2824%29%5E2-4%2A1%2A-180=1296.

Discriminant d=1296 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-24%2B-sqrt%28+1296+%29%29%2F2%5Ca.

w%5B1%5D+=+%28-%2824%29%2Bsqrt%28+1296+%29%29%2F2%5C1+=+6
w%5B2%5D+=+%28-%2824%29-sqrt%28+1296+%29%29%2F2%5C1+=+-30

Quadratic expression 1w%5E2%2B24w%2B-180 can be factored:
1w%5E2%2B24w%2B-180+=+1%28w-6%29%2A%28w--30%29
Again, the answer is: 6, -30. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B24%2Ax%2B-180+%29



With w=6, then w%2F2%2B12=15. Area A=6*15=90 which is a true statement.

Step 6. ANSWER: The dimensions of a rectangle are 6 meters and 15 meters.

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.

Good luck in your studies!

Respectfully,
Dr J





Linear-systems/221568: 4x+2y=-6
2x+3y=-3
1 solutions

Answer 166144 by drj(1380) About Me  on 2009-10-04 18:57:28 (Show Source):
You can put this solution on YOUR website!
4x+2y=-6
2x+3y=-3

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++4%5Cx+%2B+2%5Cy+=+-6%2C%0D%0A++++2%5Cx+%2B+3%5Cy+=+-3+%29%0D%0A++We'll use substitution. After moving 2*y to the right, we get:
4%2Ax+=+-6+-+2%2Ay, or x+=+-6%2F4+-+2%2Ay%2F4. Substitute that
into another equation:
2%2A%28-6%2F4+-+2%2Ay%2F4%29+%2B+3%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.

Good luck in your studies!

Respectfully,
Dr J


Problems-with-consecutive-odd-even-integers/221523: Determine whether there are two consecutive odd integers such that 5 times the first exceeds 3 times the second by 54.
1 solutions

Answer 166139 by drj(1380) About Me  on 2009-10-04 18:09:35 (Show Source):
You can put this solution on YOUR website!
Determine whether there are two consecutive odd integers such that 5 times the first exceeds 3 times the second by 54.

Step 1. Let n be the first odd integer.

Step 2. Let n+2 be then next consecutive odd integer.

Step 3. Let 5n be 5 times the first odd integer.

Step 4. Let 3(n+2) be 3 times the second odd integer.

Step 5. Then, 5n=3(n+2)+54 since 5 times the first exceeds 3 times the second by 54

Step 6. Solving the equation in Step 5 yields the following steps:

5n=3%28n%2B2%29%2B54

5n=3n%2B6%2B54

5n=3n%2B60

Subtract 3n from both sides of the equation

5n-3n=3n%2B60-3n

2n=60

Divide by 2 to both sides of the equation yields

2n%2F2=60%2F2

n=30 but n is an even integer.

Step 8. ANSWER: Therefore there are no odd integers that satisfies the given problem statement.

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.

Good luck in your studies!

Respectfully,
Dr J





Triangles/221519: The second angle of a triangle is 4 times as large as the first. The third angle is 120° more
than the sum of the other two angles. Find the measure of the second angle.
1 solutions

Answer 166134 by drj(1380) About Me  on 2009-10-04 18:01:54 (Show Source):
You can put this solution on YOUR website!
The second angle of a triangle is 4 times as large as the first. The third angle is 120° more than the sum of the other two angles. Find the measure of the second angle.

Step 1. Three angles of a triangle add up to 180 degrees.

Step 2. Let x be the first angle.

Step 3. Let 4x be the second angle since it's 4 times as large as the first.

Step 4. Let x+4x=5x be the sum of the first and second angles.

Step 5. Let 5x+120 be the third angle since it's 120 degrees more than the sum of the other two angles.

Step 6. Then, x+4x+5x+120=180 since the three angles add up to 180

Step 7. Solving the equation in Step 6 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: x=6.
  • Graphical form: Equation x%2B4x%2B5x%2B120=180 was fully solved.
  • Text form: x+4x+5x+120=180 simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+x%2B4x%2B5x%2B120=180+%29
    For tutors: simplify_cartoon( x+4x+5x+120=180 )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at highlight_red%28+x+%29%2Bhighlight_red%28+4%2Ax+%29%2Bhighlight_red%28+5%2Ax+%29%2B120=180.
Eliminated similar terms highlight_red%28+x+%29,highlight_red%28+4%2Ax+%29,highlight_red%28+5%2Ax+%29 replacing them with highlight_green%28+%281%2B4%2B5%29%2Ax+%29
It becomes highlight_green%28+%281%2B4%2B5%29%2Ax+%29%2B120=180.

Look at %28highlight_red%28+1+%29%2Bhighlight_red%28+4+%29%2Bhighlight_red%28+5+%29%29%2Ax%2B120=180.
Added fractions or integers together
It becomes %28highlight_green%28+10+%29%29%2Ax%2B120=180.

Look at highlight_red%28+%28highlight_red%28+10+%29%29%2Ax+%29%2B120=180.
Remove unneeded parentheses around factor highlight_red%28+10+%29
It becomes highlight_green%28+10+%29%2Ax%2B120=180.

Look at 10%2Ax%2B120=highlight_red%28+180+%29.
Moved these terms to the left highlight_green%28+-180+%29
It becomes 10%2Ax%2B120-highlight_green%28+180+%29=0.

Look at 10%2Ax%2Bhighlight_red%28+120+%29-highlight_red%28+180+%29=0.
Added fractions or integers together
It becomes 10%2Ax%2Bhighlight_green%28+-60+%29=0.

Look at 10%2Ax%2Bhighlight_red%28+-60+%29=0.
Removed extra sign in front of -60
It becomes 10%2Ax-highlight_green%28+60+%29=0.

Look at highlight_red%28+10%2Ax-60+%29=0.
Solved linear equation highlight_red%28+10%2Ax-60=0+%29 equivalent to 10*x-60 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: x=6.

Universal Simplifier and Solver


Done!



With x=6, then 4x=24 and 5x+120=150. Note these angles add up to 180 degrees.

Step 8. ANSWER: The three angles are 6 degrees, 24 degrees and 150 degrees.

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.