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Quadratic_Equations/213902: Solve by using the quadratic formula.
(18/w^2) - (10/w) + 1 = 0
If your answer contains a radical, express it in simplified form.
1 solutions

Answer 161562 by drj(1380) About Me  on 2009-09-15 18:14:23 (Show Source):
You can put this solution on YOUR website!
Solve by using the quadratic formula.


%2818%2Fw%5E2%29+-+%2810%2Fw%29+%2B+1+=+0


If your answer contains a radical, express it in simplified form.

Step 1. Multiply above equation by w%5E2 to get rid of the denominator terms.


w%5E2%2A%28%2818%2Fw%5E2%29+-+%2810%2Fw%29+%2B+1%29+=+0

%2818+-+10w+%2B+w%5E2%29+=+0 or

w%5E2-10w%2B18+=+0

Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B-10x%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=%28-10%29%5E2-4%2A1%2A18=28.

Discriminant d=28 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--10%2B-sqrt%28+28+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-10%29%2Bsqrt%28+28+%29%29%2F2%5C1+=+7.64575131106459
x%5B2%5D+=+%28-%28-10%29-sqrt%28+28+%29%29%2F2%5C1+=+2.35424868893541

Quadratic expression 1x%5E2%2B-10x%2B18 can be factored:
1x%5E2%2B-10x%2B18+=+1%28x-7.64575131106459%29%2A%28x-2.35424868893541%29
Again, the answer is: 7.64575131106459, 2.35424868893541. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-10%2Ax%2B18+%29



Based on the above steps the solutions simplify the solutions as follows:

x1=%2810%2Bsqrt28%29%2F2=5%2Bsqrt%287%2A4%29%2F2=5%2B2sqrt%287%29%2F2=5%2Bsqrt7%29

x1=%2810-sqrt28%29%2F2=5-sqrt%287%2A4%29%2F2=5-2sqrt%287%29%2F2=5-sqrt7%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


Linear-systems/213899: This question is from textbook algebra 2
how to solve linear systems algebraically
problem: 6x-y=-2
-18x+3y=4
1 solutions

Answer 161560 by drj(1380) About Me  on 2009-09-15 18:02:03 (Show Source):
You can put this solution on YOUR website!
6x-y=-2 or y=6x%2B2
-18x%2B3y=4

Step 1. Let's rewrite the second equation where we can again rearrange by adding 18x to both sides of the equation to yield

3y=18x%2B4

or dividing by 3 to both sides of the equation, we have

y=6x%2B4%2F3

Step 2. Now compare the following equivalent system of equations

y=6x%2B2
y=6x%2B4%2F3

The above equations are in slope intercept form where m=6 for both equations.

Step 3. ANSWER: When the equations of lines have the same slope there is NO SOLUTION since they cannot intersect at a point.

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


Linear-equations/213898: find an equation for the line with y intercept 0 that is parallel yo y=2x-5.
1 solutions

Answer 161559 by drj(1380) About Me  on 2009-09-15 17:45:34 (Show Source):
You can put this solution on YOUR website!
Find an equation for the line with y intercept 0 that is parallel yo y=2x-5.

Step 1. Lines are parallel is when the slopes are equal. The slope of y=2x-5 is in slope intercept form given as y=mx+b where m is the slope and b is the y-intercept. For this example slope m=2 and y-intercept b=-5

Step 2. So the slope is m=2. We are given b=0 for the problem statement for the unknown line.

Step 3. Therefore, the equation is y=2x (ANSWER) and is parallel with y=2x-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


Matrices-and-determiminant/213891: 2x+3y=-3
x+2y=2
This is the problem and my daughters teacher gave her this: -2R1+R2
Please explain how this is done
1 solutions

Answer 161557 by drj(1380) About Me  on 2009-09-15 17:15:42 (Show Source):
You can put this solution on YOUR website!
2x+3y=-3
x+2y=2

The following solves the system of linear equations by substitution.

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++2%5Cx+%2B+3%5Cy+=+-3%2C%0D%0A++++1%5Cx+%2B+2%5Cy+=+2+%29%0D%0A++We'll use substitution. After moving 3*y to the right, we get:
2%2Ax+=+-3+-+3%2Ay, or x+=+-3%2F2+-+3%2Ay%2F2. Substitute that
into another equation:
1%2A%28-3%2F2+-+3%2Ay%2F2%29+%2B+2%5Cy+=+2 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 and I don't understand the statement: -2R1+R2

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

Trigonometry-basics/213877: find x-intercept and y- intercept and graph
3x-2y+8=0
1 solutions

Answer 161556 by drj(1380) About Me  on 2009-09-15 17:12:56 (Show Source):
You can put this solution on YOUR website!
Find x-intercept and y- intercept and graph

3x-2y%2B8=0

Step 1. x-intercept occurs when y=0 and y-intercept occurs when x=0.

Step 2. So at x=0 then

3%2A0-2y%2B8=0

8=2y

y=4 So y-intercept is 4 at point (0,4)

Step 3. At y=0 then

3x-2%2A0%2B8=0

3x=-8

x=-8%2F3 So x-intercept is -8/3 at point (-8/3,0)

Step 4. Here's the graph and note the x-intercept and y-intercept points on the graph.

Solved by pluggable solver: DESCRIBE a linear EQUATION: slope, intercepts, etc
Equation 3+x+%2B+-2+y+=+-8 describes a sloping line. For any
equation ax+by+c = 0, slope is -a%2Fb+=+-3%2F-2.
  • X intercept is found by setting y to 0: ax+by=c becomes ax=c. that means that x = c/a. -8/3 = -2.66666666666667.
  • Y intercept is found by setting x to 0: the equation becomes by=c, and therefore y = c/b. Y intercept is -8/-2 = 4.
  • Slope is -3/-2 = 1.5.
  • Equation in slope-intercept form: y=1.5*x+4.



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


Rectangles/213863: The perimeter of a square is 36 centimeters. Find the length of the diagonal.
1 solutions

Answer 161547 by drj(1380) About Me  on 2009-09-15 16:19:29 (Show Source):
You can put this solution on YOUR website!
The perimeter of a square is 36 centimeters. Find the length of the diagonal.

Step 1. Let P be the perimeter of a square which means adding up all four sides.

Step 2. Let s be the side of a square.

Step 3 Then 4s=36 or s=9 centimeters after dividing by 4 to both sides of equation.

Step 4. Use Pythagorean Theorem to find diagonal which says that the sum of the square of the legs (=s^2+s^2=2s^2) is equal to square of the hypotenuse (diagonal in this case and letting d be the diagonal).

d%5E2=s%5E2%2Bs%5E2=2s%5E2

d=sqrt%282s%5E2%29

d=sqrt%282%2A9%5E2%29

d=9%2Asqrt%282%29=12.73

Step 5. ANSWER: The length of diagonal is 9sqrt%282%29=12.73 centimeters

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


Angles/213862: two angles of a triangle measure 15 degree and 85 degree what is the measure for the third angle
1 solutions

Answer 161542 by drj(1380) About Me  on 2009-09-15 16:08:01 (Show Source):
You can put this solution on YOUR website!
Two angles of a triangle measure 15 degree and 85 degree what is the measure for the third angle

Step 1. The sum of the angles in a triangle is equal to 180 degrees.

Step 2. Let x by the unknown third angle. Then

x%2B15%2B85=180

x%2B100=180

Step 3. Subtract 100 from both sides of equation to get x

x%2B100-100=180-100

x=80 ANSWER

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/213859: A rectangle is 10 inches long and 8 inches wide, what is the length of the diangonal?
1 solutions

Answer 161538 by drj(1380) About Me  on 2009-09-15 15:59:33 (Show Source):
You can put this solution on YOUR website!
A rectangle is 10 inches long and 8 inches wide, what is the length of the diagonal?

Step 1. Use the Pythagorean Theorem where the sum of the squares of the legs (length and width) is equal to the square of the hypotenuse (diagonal).

Step 2. Let d be the diagonal, then d%5E2=10%5E2%2B8%5E2

d=sqrt%28100%2B64%29

d=12.81 ANSWER

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


Linear-systems/213849: What is the answer to this equation: 5x=+10-6x+3=6-2x-2 and can you tell me how you solved it please and thank you
1 solutions

Answer 161536 by drj(1380) About Me  on 2009-09-15 15:55:18 (Show Source):
You can put this solution on YOUR website!
What is the answer to this equation: 5x+10-6x+3=6-2x-2 and can you tell me how you solved it please and thank you

The following steps will solve the following equation: 5x%2B10-6x%2B3=6-2x-2

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


YOUR ANSWER


  • Here's what you tried:
  • This is an equation! Solutions: x=-9.
  • Graphical form: Equation 5x%2B10-6x%2B3=6-2x-2 was fully solved.
  • Text form: 5x+10-6x+3=6-2x-2 simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+5x%2B10-6x%2B3=6-2x-2+%29
    For tutors: simplify_cartoon( 5x+10-6x+3=6-2x-2 )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at 5%2Ax%2Bhighlight_red%28+10+%29-6%2Ax%2Bhighlight_red%28+3+%29=6-2x-2.
Added fractions or integers together
It becomes 5%2Ax%2Bhighlight_green%28+13+%29-6%2Ax=6-2x-2.

Look at 5%2Ax%2Bhighlight_red%28+13+%29-6%2Ax=6-2x-2.
Moved 13 to the right of expression
It becomes 5%2Ax-6%2Ax%2Bhighlight_green%28+13+%29=6-2x-2.

Look at highlight_red%28+5%2Ax+%29-highlight_red%28+6%2Ax+%29%2B13=6-2x-2.
Eliminated similar terms highlight_red%28+5%2Ax+%29,highlight_red%28+-6%2Ax+%29 replacing them with highlight_green%28+%285-6%29%2Ax+%29
It becomes highlight_green%28+%285-6%29%2Ax+%29%2B13=6-2x-2.

Look at %28highlight_red%28+5+%29-highlight_red%28+6+%29%29%2Ax%2B13=6-2x-2.
Added fractions or integers together
It becomes %28highlight_green%28+-1+%29%29%2Ax%2B13=6-2x-2.

Look at %28highlight_red%28+-1+%29%29%2Ax%2B13=6-2x-2.
Removed extra sign in front of -1
It becomes %28-highlight_green%28+1+%29%29%2Ax%2B13=6-2x-2.

Look at highlight_red%28+%28-highlight_red%28+1+%29%29%2Ax+%29%2B13=6-2x-2.
Remove unneeded parentheses around factor highlight_red%28+1+%29
It becomes -highlight_green%28+1+%29%2Ax%2B13=6-2x-2.

Look at -highlight_red%28+1+%29%2Ax%2B13=6-2x-2.
Remove extraneous '1' from product highlight_red%28+1+%29
It becomes -x%2B13=6-2x-2.

Look at -x%2B13=highlight_red%28+6+%29-2%2Ax-highlight_red%28+2+%29.
Added fractions or integers together
It becomes -x%2B13=highlight_green%28+4+%29-2%2Ax.

Look at -x%2B13=highlight_red%28+4+%29-2%2Ax.
Moved 4 to the right of expression
It becomes -x%2B13=-2%2Ax%2Bhighlight_green%28+4+%29.

Look at -x%2B13=highlight_red%28+-2%2Ax%2B4+%29.
Moved these terms to the left highlight_green%28+2%2Ax+%29,highlight_green%28+-4+%29
It becomes -x%2B13%2Bhighlight_green%28+2%2Ax+%29-highlight_green%28+4+%29=0.

Look at -x%2Bhighlight_red%28+13+%29%2B2%2Ax-highlight_red%28+4+%29=0.
Added fractions or integers together
It becomes -x%2Bhighlight_green%28+9+%29%2B2%2Ax=0.

Look at -x%2Bhighlight_red%28+9+%29%2B2%2Ax=0.
Moved 9 to the right of expression
It becomes -x%2B2%2Ax%2Bhighlight_green%28+9+%29=0.

Look at -highlight_red%28+x+%29%2Bhighlight_red%28+2%2Ax+%29%2B9=0.
Eliminated similar terms highlight_red%28+-x+%29,highlight_red%28+2%2Ax+%29 replacing them with highlight_green%28+%28-1%2B2%29%2Ax+%29
It becomes highlight_green%28+%28-1%2B2%29%2Ax+%29%2B9=0.

Look at highlight_red%28+%28-1%2B2%29+%29%2Ax%2B9=0.
Remove extraneous '1' from product highlight_red%28+%28-1%2B2%29+%29
It becomes x%2B9=0.

Look at highlight_red%28+x%2B9+%29=0.
Solved linear equation highlight_red%28+x%2B9=0+%29 equivalent to x+9 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: x=-9.

Universal Simplifier and Solver


Done!



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


Numbers_Word_Problems/213852: The sum of four consecutive even integers is 276. Find the four integers
1 solutions

Answer 161534 by drj(1380) About Me  on 2009-09-15 15:49:01 (Show Source):
You can put this solution on YOUR website!
The sum of four consecutive even integers is 276. Find the four integers.

Step 1. Let n be one even integer, n+2 the next consecutive integer, n+4 and n+6 are the next two consecutive integers.

Step 2. So n+n+2+n+4+n+6=276 as given by the problem statement.

Step 3. Solve using 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=66.
  • Graphical form: Equation n%2Bn%2B2%2Bn%2B4%2Bn%2B6=276 was fully solved.
  • Text form: n+n+2+n+4+n+6=276 simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+n%2Bn%2B2%2Bn%2B4%2Bn%2B6=276+%29
    For tutors: simplify_cartoon( n+n+2+n+4+n+6=276 )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at n%2Bn%2Bhighlight_red%28+2+%29%2Bn%2Bhighlight_red%28+4+%29%2Bn%2Bhighlight_red%28+6+%29=276.
Added fractions or integers together
It becomes n%2Bn%2Bhighlight_green%28+12+%29%2Bn%2Bn=276.

Look at n%2Bn%2Bhighlight_red%28+12+%29%2Bn%2Bn=276.
Moved 12 to the right of expression
It becomes n%2Bn%2Bn%2Bn%2Bhighlight_green%28+12+%29=276.

Look at .
Eliminated similar terms highlight_red%28+n+%29,highlight_red%28+n+%29,highlight_red%28+n+%29,highlight_red%28+n+%29 replacing them with highlight_green%28+%281%2B1%2B1%2B1%29%2An+%29
It becomes highlight_green%28+%281%2B1%2B1%2B1%29%2An+%29%2B12=276.

Look at .
Added fractions or integers together
It becomes %28highlight_green%28+4+%29%29%2An%2B12=276.

Look at highlight_red%28+%28highlight_red%28+4+%29%29%2An+%29%2B12=276.
Remove unneeded parentheses around factor highlight_red%28+4+%29
It becomes highlight_green%28+4+%29%2An%2B12=276.

Look at 4%2An%2B12=highlight_red%28+276+%29.
Moved these terms to the left highlight_green%28+-276+%29
It becomes 4%2An%2B12-highlight_green%28+276+%29=0.

Look at 4%2An%2Bhighlight_red%28+12+%29-highlight_red%28+276+%29=0.
Added fractions or integers together
It becomes 4%2An%2Bhighlight_green%28+-264+%29=0.

Look at 4%2An%2Bhighlight_red%28+-264+%29=0.
Removed extra sign in front of -264
It becomes 4%2An-highlight_green%28+264+%29=0.

Look at highlight_red%28+4%2An-264+%29=0.
Solved linear equation highlight_red%28+4%2An-264=0+%29 equivalent to 4*n-264 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: n=66.

Universal Simplifier and Solver


Done!



Step 4. So the even integers are 66, 68, 70, 72. These integers add up to 276.

I hope the above steps were helpful.

And good luck in your studies!

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.

Respectfully,
Dr J


Equations/213816: 2x +3y=6
1 solutions

Answer 161528 by drj(1380) About Me  on 2009-09-15 15:10:10 (Show Source):
You can put this solution on YOUR website!
2x+%2B3y=6

Here I assume you want to plot the line.

Step 1. Let's put it in slope-intercept form y=mx+b where m is the slope and b is the y-intercepts

2x+%2B3y=6

Step 2. Subtract -2x from both sides of equation.

2x+%2B3y-2x=6-2z

2x+%2B3y-2x=6-2z

3y=6-2x

Step 3. Divide 3 to both sides of equation

3y%2F3=%286-2x%29%2F3

y=%28-2x%29%2B2
Step 4. So y=-2x/3+2 where slope m=-2/3 and y-intercept b=2.

Solved by pluggable solver: DESCRIBE a linear EQUATION: slope, intercepts, etc
Equation 2+x+%2B+3+y+=+6 describes a sloping line. For any
equation ax+by+c = 0, slope is -a%2Fb+=+-2%2F3.
  • X intercept is found by setting y to 0: ax+by=c becomes ax=c. that means that x = c/a. 6/2 = 3.
  • Y intercept is found by setting x to 0: the equation becomes by=c, and therefore y = c/b. Y intercept is 6/3 = 2.
  • Slope is -2/3 = -0.666666666666667.
  • Equation in slope-intercept form: y=-0.666666666666667*x+2.
graph%28+500%2C+500%2C+3-8%2C+3%2B8%2C+2-8%2C+2%2B8%2C+-0.666666666666667%2Ax%2B2+%29+



I hope the above steps were helpful.

And good luck in your studies!

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.

Respectfully,
Dr J





Linear-systems/213833: x/2=3+(x-30/5)
this is the only question i dont understand too well on my homework please help
1 solutions

Answer 161525 by drj(1380) About Me  on 2009-09-15 14:28:13 (Show Source):
You can put this solution on YOUR website!
x%2F2=3%2B%28x-30%2F5%29

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%2F2=3%2B%28x-30%2F5%29 was fully solved.
  • Text form: x/2=3+(x-30/5) simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+x%2F2=3%2B%28x-30%2F5%29+%29
    For tutors: simplify_cartoon( x/2=3+(x-30/5) )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at x%2F2=3%2Bhighlight_red%28+%28x-30%2F5%29+%29.
Remove unneeded parentheses around terms highlight_red%28+x+%29,highlight_red%28+-30%2F5+%29
It becomes x%2F2=3%2Bhighlight_green%28+x+%29-highlight_green%28+30%2F5+%29.

Look at x%2F2=3%2Bx-highlight_red%28+30+%29%2Fhighlight_red%28+5+%29.
Factors 30 and 5 have greatest common factor (GCF) of 5. Reducing fraction.
It becomes x%2F2=3%2Bx-highlight_green%28+6+%29%2Fhighlight_green%28+1+%29.

Look at x%2F2=highlight_red%28+3+%29%2Bx-highlight_red%28+6%2F1+%29.
Added fractions or integers together
It becomes x%2F2=highlight_green%28+-3+%29%2Bx.

Look at x%2F2=highlight_red%28+-3+%29%2Bx.
Moved -3 to the right of expression
It becomes x%2F2=x%2Bhighlight_green%28+-3+%29.

Look at x%2F2=x%2Bhighlight_red%28+-3+%29.
Removed extra sign in front of -3
It becomes x%2F2=x-highlight_green%28+3+%29.

Look at x%2F2=highlight_red%28+x-3+%29.
Moved these terms to the left highlight_green%28+-x+%29,highlight_green%28+3+%29
It becomes x%2F2-highlight_green%28+x+%29%2Bhighlight_green%28+3+%29=0.

Look at highlight_red%28+x%2F2+%29-highlight_red%28+x+%29%2B3=0.
Eliminated similar terms highlight_red%28+x%2F2+%29,highlight_red%28+-x+%29 replacing them with highlight_green%28+%281%2F2-1%29%2Ax+%29
It becomes highlight_green%28+%281%2F2-1%29%2Ax+%29%2B3=0.

Look at %28highlight_red%28+1%2F2+%29-highlight_red%28+1+%29%29%2Ax%2B3=0.
Added fractions or integers together
It becomes %28-highlight_green%28+1%2F2+%29%29%2Ax%2B3=0.

Look at highlight_red%28+%28-highlight_red%28+1%2F2+%29%29%2Ax+%29%2B3=0.
Remove unneeded parentheses around factor highlight_red%28+1+%29,highlight_red%28+1%2F2+%29
It becomes -highlight_green%28+1+%29%2Fhighlight_green%28+2+%29%2Ax%2B3=0.

Look at -highlight_red%28+1+%29%2F2%2Ax%2B3=0.
Remove extraneous '1' from product highlight_red%28+1+%29
It becomes -x%2F2%2B3=0.

Look at highlight_red%28+-x%2F2%2B3+%29=0.
Solved linear equation highlight_red%28+-x%2F2%2B3=0+%29 equivalent to -0.5*x+3 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: x=6.

Universal Simplifier and Solver


Done!



I hope the above steps were helpful.

And good luck in your studies!

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.

Respectfully,
Dr J


Linear-systems/213834: x/2=3+(x-30/5)
this is the only question i dont understand too well on my homework please help
1 solutions

Answer 161524 by drj(1380) About Me  on 2009-09-15 14:26:50 (Show Source):
You can put this solution on YOUR website!
x%2F2=3%2B%28x-30%2F5%29

Let's solve and simplify the above equation.

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%2F2=3%2B%28x-30%2F5%29 was fully solved.
  • Text form: x/2=3+(x-30/5) simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+x%2F2=3%2B%28x-30%2F5%29+%29
    For tutors: simplify_cartoon( x/2=3+(x-30/5) )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at x%2F2=3%2Bhighlight_red%28+%28x-30%2F5%29+%29.
Remove unneeded parentheses around terms highlight_red%28+x+%29,highlight_red%28+-30%2F5+%29
It becomes x%2F2=3%2Bhighlight_green%28+x+%29-highlight_green%28+30%2F5+%29.

Look at x%2F2=3%2Bx-highlight_red%28+30+%29%2Fhighlight_red%28+5+%29.
Factors 30 and 5 have greatest common factor (GCF) of 5. Reducing fraction.
It becomes x%2F2=3%2Bx-highlight_green%28+6+%29%2Fhighlight_green%28+1+%29.

Look at x%2F2=highlight_red%28+3+%29%2Bx-highlight_red%28+6%2F1+%29.
Added fractions or integers together
It becomes x%2F2=highlight_green%28+-3+%29%2Bx.

Look at x%2F2=highlight_red%28+-3+%29%2Bx.
Moved -3 to the right of expression
It becomes x%2F2=x%2Bhighlight_green%28+-3+%29.

Look at x%2F2=x%2Bhighlight_red%28+-3+%29.
Removed extra sign in front of -3
It becomes x%2F2=x-highlight_green%28+3+%29.

Look at x%2F2=highlight_red%28+x-3+%29.
Moved these terms to the left highlight_green%28+-x+%29,highlight_green%28+3+%29
It becomes x%2F2-highlight_green%28+x+%29%2Bhighlight_green%28+3+%29=0.

Look at highlight_red%28+x%2F2+%29-highlight_red%28+x+%29%2B3=0.
Eliminated similar terms highlight_red%28+x%2F2+%29,highlight_red%28+-x+%29 replacing them with highlight_green%28+%281%2F2-1%29%2Ax+%29
It becomes highlight_green%28+%281%2F2-1%29%2Ax+%29%2B3=0.

Look at %28highlight_red%28+1%2F2+%29-highlight_red%28+1+%29%29%2Ax%2B3=0.
Added fractions or integers together
It becomes %28-highlight_green%28+1%2F2+%29%29%2Ax%2B3=0.

Look at highlight_red%28+%28-highlight_red%28+1%2F2+%29%29%2Ax+%29%2B3=0.
Remove unneeded parentheses around factor highlight_red%28+1+%29,highlight_red%28+1%2F2+%29
It becomes -highlight_green%28+1+%29%2Fhighlight_green%28+2+%29%2Ax%2B3=0.

Look at -highlight_red%28+1+%29%2F2%2Ax%2B3=0.
Remove extraneous '1' from product highlight_red%28+1+%29
It becomes -x%2F2%2B3=0.

Look at highlight_red%28+-x%2F2%2B3+%29=0.
Solved linear equation highlight_red%28+-x%2F2%2B3=0+%29 equivalent to -0.5*x+3 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: x=6.

Universal Simplifier and Solver


Done!



I hope the above steps were helpful.

And good luck in your studies!

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.

Respectfully,
Dr J



Trigonometry-basics/213742: A Building AB, is observed across a street from the window of a house 7 metres above the ground. If the angle of elevation of the top of the building is 23degrees and the angle of depression of the foot of the building is 26degrees, calculate the height of the building.
1 solutions

Answer 161506 by drj(1380) About Me  on 2009-09-15 11:25:04 (Show Source):
You can put this solution on YOUR website!
A Building AB, is observed across a street from the window of a house 7 metres above the ground. If the angle of elevation of the top of the building is 23degrees and the angle of depression of the foot of the building is 26degrees, calculate the height of the building.

Step 1. Let d be the distance to the building from the window. Given depression angle is 26 degrees and the height of the window is 7 meters, then we have the opposite side is 7 and the adjacent side is x. In this case, we have

tan%2826%29=7%2Fd

d=14.3 metres

Step 2. Let x = be the height above seven metre reference, then total height of building h=x+. Then from the window looking at the building we have an angle of elevation of 23 degrees. Then the opposite side is x and the adjacent side is d. We have

tan%2823%29=x%2Fd=x%2F14.3

x=14.3tan%2823%29

x=6.07+metres

Step 3. Then h=6.07+7=13.07 or 13.07 metres

I hope the above steps were helpful.

And good luck in your studies!

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.

Respectfully,
Dr J


Equations/213777: 1. x^3+216=0


2. 5x^3+30x^2+45x=0


3. 1/x^2+8/x+15=0

1 solutions

Answer 161503 by drj(1380) About Me  on 2009-09-15 11:06:12 (Show Source):
You can put this solution on YOUR website!
1. x^3+216=0

x%5E3%2B216-216=0-216 Subtracting 216 from both sides of equation

x%5E3=-216

x=-6 Answer

2. 5x^3+30x^2+45x=0

x%285x%5E2%2B30x%2B45%29=0

x%285x%2B+15%29%28x%2B3%29+=+0+

where we have x=0, 5x+15=0 and x+3=0. Solving yields

x=0, x=-3 and x=-3, or solve quadratic equation using following steps,

Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 5x%5E2%2B30x%2B45+=+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=%2830%29%5E2-4%2A5%2A45=0.

Discriminant d=0 is zero! That means that there is only one solution: x+=+%28-%2830%29%29%2F2%5C5.
Expression can be factored: 5x%5E2%2B30x%2B45+=+5%28x--3%29%2A%28x--3%29

Again, the answer is: -3, -3. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+5%2Ax%5E2%2B30%2Ax%2B45+%29




3. 1/x^2+8/x+15=0 Multiply by x^2 to get rid of denominator

x%5E2%281%2Fx%5E2%2B8%2Fx%2B15%29%2Ax%5E2=0

1%2B8x%2B15x%5E2=0

%285x%2B1%29%283x%2B1%29=0

where we have 5x+1=0 and 3x+1=0. Solving yields

So x=(-1/5) and x=(-1/3)

We can also use the quadratic formula as follows:

Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 15x%5E2%2B8x%2B1+=+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=%288%29%5E2-4%2A15%2A1=4.

Discriminant d=4 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-8%2B-sqrt%28+4+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%288%29%2Bsqrt%28+4+%29%29%2F2%5C15+=+-0.2
x%5B2%5D+=+%28-%288%29-sqrt%28+4+%29%29%2F2%5C15+=+-0.333333333333333

Quadratic expression 15x%5E2%2B8x%2B1 can be factored:
15x%5E2%2B8x%2B1+=+15%28x--0.2%29%2A%28x--0.333333333333333%29
Again, the answer is: -0.2, -0.333333333333333. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+15%2Ax%5E2%2B8%2Ax%2B1+%29



I hope the above steps were helpful.

And good luck in your studies!

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.

Respectfully,
Dr J


Functions/213768: Is a circle a 'function' - it does not pass the vertical line test. tks!

1 solutions

Answer 161494 by drj(1380) About Me  on 2009-09-15 09:48:06 (Show Source):
You can put this solution on YOUR website!
Is a circle a 'function' - it does not pass the vertical line test. tks!

Yes. You are correct. But it is an equation like x%5E2%2By%5E2=1 centered at (0,0) or radius 1. So at x=0 then y has two possible values at +1 and -1.

Hope that was helpful!.

I hope the above steps were helpful.

And good luck in your studies!

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.

Respectfully,
Dr J


logarithm/211994: find an expression or equation that is equivalent to the one given:
log(3)-log(3)9
1 solutions

Answer 161483 by drj(1380) About Me  on 2009-09-15 08:43:53 (Show Source):
You can put this solution on YOUR website!
Find an expression or equation that is equivalent to the one given:

log(3)-log(3)9

Factor out log(3) to get

(1-9)log(3)=-8log(3)= -3.187 ANSWER

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


Sequences-and-series/211895: what is the 20th term for this set of numbers? 12, 19,26, 33
1 solutions

Answer 161482 by drj(1380) About Me  on 2009-09-15 08:40:03 (Show Source):
You can put this solution on YOUR website!
What is the 20th term for this set of numbers? 12, 19,26, 33

Step 1. Look for a pattern. In this case the next number is 7 greater than the previous number.

Step 2. Here's a formula for this set of numbers:

12%2B7%2A%28n-1%29 so if n=1 then expression is 12 if n=2 then expression is 19.

Step 3. Let n=20, then

12%2B7%2A%2820-1%29=145

Step 4. ANSWER: The 20th term is 145

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


Angles/213731: Two angles are complementary. The larger of the two is 9 degrees more than twice the smaller. Find the 2 angles.
1 solutions

Answer 161481 by drj(1380) About Me  on 2009-09-15 08:31:14 (Show Source):
You can put this solution on YOUR website!
Two angles are complementary. The larger of the two is 9 degrees more than twice the smaller. Find the 2 angles.

Step 1. Complementary angles is when 2 angles add up to 90 degrees.

Step 2. x is one angle and 2x+9

Step 3. Then x+2x+9=90

Step 4. Solve the above equation using 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=27.
  • Graphical form: Equation x%2B2x%2B9=90 was fully solved.
  • Text form: x+2x+9=90 simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+x%2B2x%2B9=90+%29
    For tutors: simplify_cartoon( x+2x+9=90 )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at highlight_red%28+x+%29%2Bhighlight_red%28+2%2Ax+%29%2B9=90.
Eliminated similar terms highlight_red%28+x+%29,highlight_red%28+2%2Ax+%29 replacing them with highlight_green%28+%281%2B2%29%2Ax+%29
It becomes highlight_green%28+%281%2B2%29%2Ax+%29%2B9=90.

Look at %28highlight_red%28+1+%29%2Bhighlight_red%28+2+%29%29%2Ax%2B9=90.
Added fractions or integers together
It becomes %28highlight_green%28+3+%29%29%2Ax%2B9=90.

Look at highlight_red%28+%28highlight_red%28+3+%29%29%2Ax+%29%2B9=90.
Remove unneeded parentheses around factor highlight_red%28+3+%29
It becomes highlight_green%28+3+%29%2Ax%2B9=90.

Look at 3%2Ax%2B9=highlight_red%28+90+%29.
Moved these terms to the left highlight_green%28+-90+%29
It becomes 3%2Ax%2B9-highlight_green%28+90+%29=0.

Look at 3%2Ax%2Bhighlight_red%28+9+%29-highlight_red%28+90+%29=0.
Added fractions or integers together
It becomes 3%2Ax%2Bhighlight_green%28+-81+%29=0.

Look at 3%2Ax%2Bhighlight_red%28+-81+%29=0.
Removed extra sign in front of -81
It becomes 3%2Ax-highlight_green%28+81+%29=0.

Look at highlight_red%28+3%2Ax-81+%29=0.
Solved linear equation highlight_red%28+3%2Ax-81=0+%29 equivalent to 3*x-81 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: x=27.

Universal Simplifier and Solver


Done!




Step 5. ANSWER: The angles are x=27 degrees and 2x+9=2(27)+9=63 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


Equations/213745: -4(a+1)-3a=7(2a-3)+3
1 solutions

Answer 161480 by drj(1380) About Me  on 2009-09-15 08:26:39 (Show Source):
You can put this solution on YOUR website!
-4%28a%2B1%29-3a=7%282a-3%29%2B3

The following steps will solve the above problem

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


YOUR ANSWER


  • Here's what you tried:
  • This is an equation! Solutions: a=0.666666666666667.
  • Graphical form: Equation -4%2A%28a%2B1%29-3a=7%2A%282a-3%29%2B3 was fully solved.
  • Text form: -4*(a+1)-3a=7*(2a-3)+3 simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+-4%2A%28a%2B1%29-3a=7%2A%282a-3%29%2B3+%29
    For tutors: simplify_cartoon( -4*(a+1)-3a=7*(2a-3)+3 )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at -4%2A%28a%2B1%29-3%2Aa=highlight_red%28+7%2A%282%2Aa-3%29%2B3+%29.
Moved these terms to the left highlight_green%28+-7%2A%282%2Aa-3%29+%29,highlight_green%28+-3+%29
It becomes -4%2A%28a%2B1%29-3%2Aa-highlight_green%28+7%2A%282%2Aa-3%29+%29-highlight_green%28+3+%29=0.

Look at -highlight_red%28+4%2A%28a%2B1%29+%29-3%2Aa-7%2A%282%2Aa-3%29-3=0.
Expanded term -4 by using associative property on %28a%2B1%29
It becomes -highlight_green%28+4%2Aa+%29-highlight_green%28+4%2A1+%29-3%2Aa-7%2A%282%2Aa-3%29-3=0.

Look at -4%2Aa-highlight_red%28+4+%29%2Ahighlight_red%28+1+%29-3%2Aa-7%2A%282%2Aa-3%29-3=0.
Multiplied numerator integers
It becomes -4%2Aa-highlight_green%28+4+%29-3%2Aa-7%2A%282%2Aa-3%29-3=0.

Look at -4%2Aa-highlight_red%28+4+%29-3%2Aa-7%2A%282%2Aa-3%29-highlight_red%28+3+%29=0.
Added fractions or integers together
It becomes -4%2Aa%2Bhighlight_green%28+-7+%29-3%2Aa-7%2A%282%2Aa-3%29=0.

Look at -4%2Aa%2Bhighlight_red%28+-7+%29-3%2Aa-7%2A%282%2Aa-3%29=0.
Moved -7 to the right of expression
It becomes -4%2Aa-3%2Aa-7%2A%282%2Aa-3%29%2Bhighlight_green%28+-7+%29=0.

Look at -4%2Aa-3%2Aa-7%2A%282%2Aa-3%29%2Bhighlight_red%28+-7+%29=0.
Removed extra sign in front of -7
It becomes -4%2Aa-3%2Aa-7%2A%282%2Aa-3%29-highlight_green%28+7+%29=0.

Look at -highlight_red%28+4%2Aa+%29-highlight_red%28+3%2Aa+%29-7%2A%282%2Aa-3%29-7=0.
Eliminated similar terms highlight_red%28+-4%2Aa+%29,highlight_red%28+-3%2Aa+%29 replacing them with highlight_green%28+%28-4-3%29%2Aa+%29
It becomes highlight_green%28+%28-4-3%29%2Aa+%29-7%2A%282%2Aa-3%29-7=0.

Look at %28-highlight_red%28+4+%29-highlight_red%28+3+%29%29%2Aa-7%2A%282%2Aa-3%29-7=0.
Added fractions or integers together
It becomes %28highlight_green%28+-7+%29%29%2Aa-7%2A%282%2Aa-3%29-7=0.

Look at %28highlight_red%28+-7+%29%29%2Aa-7%2A%282%2Aa-3%29-7=0.
Removed extra sign in front of -7
It becomes %28-highlight_green%28+7+%29%29%2Aa-7%2A%282%2Aa-3%29-7=0.

Look at highlight_red%28+%28-highlight_red%28+7+%29%29%2Aa+%29-7%2A%282%2Aa-3%29-7=0.
Remove unneeded parentheses around factor highlight_red%28+7+%29
It becomes -highlight_green%28+7+%29%2Aa-7%2A%282%2Aa-3%29-7=0.

Look at -7%2Aa-highlight_red%28+7%2A%282%2Aa-3%29+%29-7=0.
Expanded term -7 by using associative property on %282%2Aa-3%29
It becomes -7%2Aa-highlight_green%28+7%2A2%2Aa+%29%2Bhighlight_green%28+7%2A3+%29-7=0.

Look at -7%2Aa-highlight_red%28+7+%29%2Ahighlight_red%28+2+%29%2Aa%2B7%2A3-7=0.
Multiplied numerator integers
It becomes -7%2Aa-highlight_green%28+14+%29%2Aa%2B7%2A3-7=0.

Look at -7%2Aa-14%2Aa%2Bhighlight_red%28+7+%29%2Ahighlight_red%28+3+%29-7=0.
Multiplied numerator integers
It becomes -7%2Aa-14%2Aa%2Bhighlight_green%28+21+%29-7=0.

Look at -7%2Aa-14%2Aa%2Bhighlight_red%28+21+%29-highlight_red%28+7+%29=0.
Added fractions or integers together
It becomes -7%2Aa-14%2Aa%2Bhighlight_green%28+14+%29=0.

Look at -highlight_red%28+7%2Aa+%29-highlight_red%28+14%2Aa+%29%2B14=0.
Eliminated similar terms highlight_red%28+-7%2Aa+%29,highlight_red%28+-14%2Aa+%29 replacing them with highlight_green%28+%28-7-14%29%2Aa+%29
It becomes highlight_green%28+%28-7-14%29%2Aa+%29%2B14=0.

Look at %28-highlight_red%28+7+%29-highlight_red%28+14+%29%29%2Aa%2B14=0.
Added fractions or integers together
It becomes %28highlight_green%28+-21+%29%29%2Aa%2B14=0.

Look at %28highlight_red%28+-21+%29%29%2Aa%2B14=0.
Removed extra sign in front of -21
It becomes %28-highlight_green%28+21+%29%29%2Aa%2B14=0.

Look at highlight_red%28+%28-highlight_red%28+21+%29%29%2Aa+%29%2B14=0.
Remove unneeded parentheses around factor highlight_red%28+21+%29
It becomes -highlight_green%28+21+%29%2Aa%2B14=0.

Look at highlight_red%28+-21%2Aa%2B14+%29=0.
Solved linear equation highlight_red%28+-21%2Aa%2B14=0+%29 equivalent to -21*a+14 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: a=0.666666666666667.

Universal Simplifier and Solver


Done!



ANSWER is 2%2F3 or 0.666667

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


Equations/213746: 1/5(2x-7)=3/10x+5
1 solutions

Answer 161478 by drj(1380) About Me  on 2009-09-15 08:23:30 (Show Source):
You can put this solution on YOUR website!
%282x-7%29%2F5=3x%2F10%2B5

Step 1. Multiply by 10 to both sides of equation to get rid of denominator.

10%2A%282x-7%29%2F5=10%2A%283x%2F10%2B5%29

2%2A%282x-7%29=3x%2B50

4x-14=3x%2B50

Step 2. add 14-3x to both sides of equation to isolate x on left side and number on right side of equation

4x-14%2B14-3x=3x%2B50%2B14-3x

x=64 ANSWER

I hope the above steps were helpful.

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Respectfully,
Dr J









Finance/213753: 5/8x+3/5=8
1 solutions

Answer 161476 by drj(1380) About Me  on 2009-09-15 08:16:03 (Show Source):
You can put this solution on YOUR website!
5x%2F8%2B3%2F5=8

Step 1. Multiply by 40 to both sides to get rid of denominator

40%2A%285x%2F8%2B3%2F5%29=40%2A8

25x%2B24=320

Step 2. Subtract 24 from both sides of equation.

25x%2B24-24=320-24

25x=296

Step 3. Divide by 25 to both sides of equation.

25x%2F25=296%2F25

x=296%2F25

I hope the above steps were helpful.

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Respectfully,
Dr J




Equations/213726: Gold has a density of 19.3g/cm^3. What is the mass in kilograms of one cubic meter of gold?
1 solutions

Answer 161457 by drj(1380) About Me  on 2009-09-14 23:48:59 (Show Source):
You can put this solution on YOUR website!
Gold has a density of 19.3g/cm^3. What is the mass in kilograms of one cubic meter of gold?

Step 1. 1 kg = 1000 g and 1 m = 100 cm

Step 2. 19.3 g/cm^3 * 1kg/1000g * ((100)^3 cm^3/(1 m^3))* 1 m^3 = 19.3*1000000/1000 = 19.3*1000 kg = 1.93 x 10^4 kg

Step 3. ANSWER is 19,300 kg

I hope the above steps were helpful.

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Respectfully,
Dr J







Linear-equations/211951: 3x-y=-13
2x+y=-9
1 solutions

Answer 161455 by drj(1380) About Me  on 2009-09-14 23:37:24 (Show Source):
You can put this solution on YOUR website!
3x-y=-13
2x%2By=-9

The following solves the system of equations by substitution.

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++3%5Cx+%2B+-1%5Cy+=+13%2C%0D%0A++++2%5Cx+%2B+1%5Cy+=+-9+%29%0D%0A++We'll use substitution. After moving -1*y to the right, we get:
3%2Ax+=+13+-+-1%2Ay, or x+=+13%2F3+-+-1%2Ay%2F3. Substitute that
into another equation:
2%2A%2813%2F3+-+-1%2Ay%2F3%29+%2B+1%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.

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Respectfully,
Dr J

Linear-equations/213723: This question is from textbook algebra one interactions course 2
use x- and y intercepts to draw the graph for 3x - y = 6
1 solutions

Answer 161454 by drj(1380) About Me  on 2009-09-14 23:34:37 (Show Source):
You can put this solution on YOUR website!
Use x- and y intercepts to draw the graph for 3x - y = 6

Step 1. The y-intercept occurs when x=0. We have

3%2A0-y=6

y=-6 so we have (0,-6) as one point on the line

Step 2. The x-intercept occurs when y=0. We have

3x-0=6

{{x=2}}} so we have (2,0) as another point on the line.

Step 3. Using these points, we can graph as follows:

Solved by pluggable solver: DESCRIBE a linear EQUATION: slope, intercepts, etc
Equation 3+x+%2B+-1+y+=+6 describes a sloping line. For any
equation ax+by+c = 0, slope is -a%2Fb+=+-3%2F-1.
  • X intercept is found by setting y to 0: ax+by=c becomes ax=c. that means that x = c/a. 6/3 = 2.
  • Y intercept is found by setting x to 0: the equation becomes by=c, and therefore y = c/b. Y intercept is 6/-1 = -6.
  • Slope is -3/-1 = 3.
  • Equation in slope-intercept form: y=3*x+-6.
graph%28+500%2C+500%2C+2-8%2C+2%2B8%2C+-6-8%2C+-6%2B8%2C+3%2Ax%2B-6+%29+



Step 4. Observe the points (2,0) and (0,-6) that are on the line and how it intercepts the axis.

I hope the above steps were helpful.

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Respectfully,
Dr J


Radicals/213722: please simplify radical.

square root of five sixths . the square root of five over 2.

Thank you
1 solutions

Answer 161452 by drj(1380) About Me  on 2009-09-14 23:23:52 (Show Source):
You can put this solution on YOUR website!
Please simplify radical.

Square root of five sixths times the square root of five over 2.

sqrt%285%2F6%29%2Asqrt%285%2F2%29=sqrt%2825%2F12%29=5%2Fsqrt%284%2A3%29

5%2F2sqrt%283%29=%285%2F2sqrt%283%29%29%2A%28sqrt%283%29%2Fsqrt%283%29%29

5sqrt%283%29%2F%282%2A3%29=5sqrt%283%29%2F6

I hope the above steps were helpful.

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Good luck in your studies!

Respectfully,
Dr J


Equations/213688: The speed limit on a certain highway is 72 km/h. What is the speed in cm/s?
1 solutions

Answer 161451 by drj(1380) About Me  on 2009-09-14 23:14:14 (Show Source):
You can put this solution on YOUR website!
The speed limit on a certain highway is 72 km/h. What is the speed in cm/s?

Step 1. 1000 m = 1 km and 100 cm= 1 m or 10000 cm = 1 km

Step 2. 72 km/h * 1000 m/km * 100 cm/m = 7,200,000 cm/h (note the units cancel in km and m when multiplying the units together.

Step 3. Answer is 7.2 million cm/h

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/213715: This question is from textbook MATHPOWER 11
Solve by elimination. Check each solution.
21. 6x-5y=-3
2y-9x=-1
Please help me out ive been stuck on this one for a while!
1 solutions

Answer 161449 by drj(1380) About Me  on 2009-09-14 23:08:01 (Show Source):
You can put this solution on YOUR website!
6x-5y=-3
2y-9x=-1

Step 1. Rearrange to align the x and y terms.

6x-5y=-3 multiply by 3 to both sides to get 18x
-9x%2B2y=-1 multiply by 2 to both sides to get -18x

18x-15y=-9 Eq 1
-18x%2B4y=-2 Eq 2

Step 2. Adding above equations Eq 1 and Eq 2 yields

-11y=-11 or y=1

Step 3. Substitute y=1 into 6x-5y=-3 yields

6x-5%281%29=-3

6x=-3%2B5

6x%2F6=2%2F6

x=1%2F3

Step 4. The solution is x=1%2F3 and y=1.

Step 5. To verify, the following will solve the linear systems using substitution.

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



Step 6. Same result...the solution is x=1%2F3 and y=1.

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


Polynomials-and-rational-expressions/213564: Simplify the rational expression:
6y
- --
46
1 solutions

Answer 161368 by drj(1380) About Me  on 2009-09-14 18:43:58 (Show Source):
You can put this solution on YOUR website!
Simplify the rational expression:

-6y%2F46=-3%2A2y%2F%2823%2A2%29=-3y%2F23

I hope the above steps were helpful.

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Respectfully,
Dr J


Radicals/213584: please help me simplify radical.

the square root of two thirds and the square root of three fourths.

studying for a chapter test tomorrow.
1 solutions

Answer 161367 by drj(1380) About Me  on 2009-09-14 18:41:57 (Show Source):
You can put this solution on YOUR website!
Simplify the square root of two thirds and the square root of three fourths.

Step 1. The idea is to get rid of the radical in the denominator by multiplying by the radical itself as follows



where we multiplied by 1=sqrt%283%29%2Fsqrt%283%29 in the above equation.

Step 2. Simplify the denominator for sqrt%283%2F4%29=sqrt%283%29%2F2 where

sqrt%284%29=sqrt%282%5E2%29=2

I hope the above steps were helpful.

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Respectfully,
Dr J




Sequences-and-series/213568: Please help me find 2 consecutive even integers whose sum is 217. The best I got was 106.6 and 108.8 but still fall short. I have these a lot and need to know how to find these with a simple math trick or formula. (Algebra 1) Thanks
1 solutions

Answer 161365 by drj(1380) About Me  on 2009-09-14 18:34:48 (Show Source):
You can put this solution on YOUR website!
Find 2 consecutive even integers whose sum is 217.

Step 1. Let n be one odd integer and n+2 be the next consecutive odd integer

Step 2. Note: The sum of two even integers is always even. So in this example there is no solution since 217 is odd.

Step 3. Solve anyway as n+n+2=217 or 2n+2=217

Step 4. 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=107.5.
  • Graphical form: Equation 2n%2B2=217 was fully solved.
  • Text form: 2n+2=217 simplifies to 0=0
  • Cartoon (animation) form: simplify_cartoon%28+2n%2B2=217+%29
    For tutors: simplify_cartoon( 2n+2=217 )
  • If you have a website, here's a link to this solution.

DETAILED EXPLANATION


Look at 2%2An%2B2=highlight_red%28+217+%29.
Moved these terms to the left highlight_green%28+-217+%29
It becomes 2%2An%2B2-highlight_green%28+217+%29=0.

Look at 2%2An%2Bhighlight_red%28+2+%29-highlight_red%28+217+%29=0.
Added fractions or integers together
It becomes 2%2An%2Bhighlight_green%28+-215+%29=0.

Look at 2%2An%2Bhighlight_red%28+-215+%29=0.
Removed extra sign in front of -215
It becomes 2%2An-highlight_green%28+215+%29=0.

Look at highlight_red%28+2%2An-215+%29=0.
Solved linear equation highlight_red%28+2%2An-215=0+%29 equivalent to 2*n-215 =0
It becomes highlight_green%28+0+%29=0.
Result: 0=0
This is an equation! Solutions: n=107.5.

Universal Simplifier and Solver


Done!



Step 5. ANSWER: NO SOLUTION

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