Simplify. (Warning: numerator and denominator must be factored!))

Got it !

 $\frac{a(b-c)}{d(c-b)} =$ $\frac{a(b-c)}{-d(b-c)} = -\frac{a}{d}$ $\frac{a}{a^2+ab}=$ $\frac{1a}{a(a+b)} = \frac{1}{a+b}$