Answer:
remember
(ab)/(ac)=b/c
find common factor
factor them
x^2-4x-32=(x-8)(x+4)
x^2+7x+12=(x+3)(x+4)
so
\frac{x^2-4x-32}{x^2+7x+12}= \frac{(x-8)(x+4)}{(x+3)(x+4)}= \frac{x-8}{x+3}
