SOLUTION: I am confused on how to simplify this fraction. The text book says the answer is not 2x-8, which is what I would have come up with. It says, "choose the value of X to show that

Algebra ->  Equations -> SOLUTION: I am confused on how to simplify this fraction. The text book says the answer is not 2x-8, which is what I would have come up with. It says, "choose the value of X to show that      Log On


   

Question 247085:
I am confused on how to simplify this fraction. The text book says the answer is not 2x-8, which is what I would have come up with. It says, "choose the value of X to show that this answer is not true." I am confused. The problem is:
2X^2-32/x-4

Thanks, Lynda (attempting to teach my son algebra)
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!

2X^2-32/x-4
.
Factoring a 2 from the numerator:
[2(X^2-16)]/x-4
[2(X+4)(X-4)]/x-4
Canceling x-4:
2(X+4)
2X+8
.
This will NOT be true if X=4 -- notice the denominator goes to zero making it undefined.