SOLUTION: Please help me with one more, very confusing. simplify: x-4/x-7-x+1/x+7+x-49/x^2-49 Thank you Gina

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Question 461985: Please help me with one more, very confusing. simplify:
x-4/x-7-x+1/x+7+x-49/x^2-49
Thank you
Gina

Answer by katealdridge(100) About Me  (Show Source):
You can put this solution on YOUR website!
%28x-4%29%2F%28x-7%29-%28x%2B1%29%2F%28x%2B7%29%2B%28x-49%29%2F%28x%5E2-49%29
First factor all polynomials that are factorable.
%28x-4%29%2F%28x-7%29-%28x%2B1%29%2F%28x%2B7%29%2B%28x-49%29%2F%28%28x-7%29%28x%2B7%29%29
Next you need to find a common denominator. It is (x+7)(x-7). So you need to multiply the first fraction by %28x%2B7%29%2F%28x%2B7%29 and the second fraction by %28x-7%29%2F%28x-7%29

Now, FOIL the numerators.
%28x%2B7%29%28x-4%29=x%5E2%2B3x-28 and %28x-7%29%28x%2B1%29=x%5E2-6x-7

Now combine the numerators.
%28x%5E2%2B3x-28-x%5E2%2B6x%2B7%2Bx-49%29%2F%28%28x%2B7%29%28x-7%29%29
Combine like terms in the numerator.
%2810x-70%29%2F%28%28x%2B7%29%28x-7%29%29
Now you should factor the numerator in case there is a possibility of canceling.
%2810%28x-7%29%29%2F%28%28x%2B7%29%28x-7%29%29
You can cancel the (x-7) on the top with the one on the bottom.
%2810%29%2F%28x%2B7%29
*Note:For these types of problems, how to leave your answer depends on your teacher's preference. Sometimes they like you to multiply everything back together instead of leaving it in the factored form. Sometimes they don't care and prefer it to stay in factored form. In this case, there is only one way to leave your answer, but I thought I'd note that for other problems.
Sorry about my first incomplete response, I hit the "post" button, instead of the "edit" button.
Kate