Question

Add and simplify:
2/x^2-16 + 3/x^2 -2x-8

Now if the numerator of your answer equals 6, what does x equal?

My answer of 5x+16/(x-4)(x+4)(x+2) does not match theirs. The correct answer is -2. I don't know how they got there.

Answer 1

yes, you got the right answer for simplifying it.
2/(x^2-16) + 3/(x^2 -2x-8) = 5x+16/(x-4)(x+4)(x+2)

but the question says that if numerator is equal to 6, what is x? thus we equate the numerator to 6:
5x + 16 = 6
5x = 6-16
5x = -10
x = -2

hope this helps~ :)