CPM Homework Help : PCT Problem 2-114

Simplify the following rational expressions.

$\frac{4x^2-8x}{x^2-9}\cdot\frac{x^2-x-12}{2x^3-8x^2}$
Hint (a):
Factor all of the expressions. Then simplify.
Step (a):
$\frac{4x(x-2)}{(x-3)(x+3)}\cdot\frac{(x-4)(x+3)}{2x^2(x-4)}$

$(x^2-y^2)\frac{4x^2+4xy}{x^2+2xy+y^2}$
Hint (b):
Write $\left(x^2-y^2\right)$ over $1$ . Then follow the same process as shown in part (a).