SOLUTION: Solve: {{{(10)/(a-7) = (-4)/(a+4)}}}

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Question 225860: Solve: %2810%29%2F%28a-7%29+=+%28-4%29%2F%28a%2B4%29
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
Solve: %2810%29%2F%28a-7%29+=+%28-4%29%2F%28a%2B4%29

Step 1. Multiply by (a-7)(a+4) to both sides of the equation to get rid of denominators.

%2810%29%28a-7%29%28a%2B4%29%2F%28a-7%29+=+%28-4%29%28a-7%29%28a%2B4%29%2F%28a%2B4%29

10%28a%2B4%29=-4%28a-7%29

10a%2B40=-4a%2B28

Step 2. Add 4a-40 to both sides of the equation to get numbers on one side and variables on the other side.

10a%2B40%2B4a-40=-4a%2B28%2B4a-40

14a=-12

Step 3. Divide by 14 to both sides of the equation to get a.


14a%2F14=-12%2F14

a=-12%2F14

a=-6%2F7

Step 4. Check solution with original equation %2810%29%2F%28a-7%29+=+%28-4%29%2F%28a%2B4%29 to see if it leads to a true statement.

%2810%29%2F%28-6%2F7-7%29+=+%28-4%29%2F%28-6%2F7%2B4%29

10%2F%28%28-6-49%29%2F7%29=%28-4%29%2F%28%28-6%2B28%29%2F7%29


10%2F%28-55%2F7%29=%28-4%29%2F%2822%2F7%29

-70%2F55=-28%2F22

-14%2F11=-14%2F11 which is a true statement.

Step 5. ANSWER is a=-6%2F7


I hope the above steps were helpful.

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

And good luck in your studies!

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