# How do you combine (y/(4y+8)) - (1/(y^2+2y))?

$f \left(y\right) = \frac{y}{4 \left(y + 2\right)} - \frac{1}{y \left(y + 2\right)} =$
= ( y^2 - 4)/[4y(y + 2) = ((y - 2)(y + 2))/(4y(y + 2) = $\frac{y - 2}{4 y}$