Answer
2
Work Step by Step
$\int^4_0 \int^{(y/2)-1}_{y/2} (x-\frac{y}{2}) dx $ dy
=$\int^4_0 [\frac{x^2}{2}-\frac{xy}{2}]^{\frac{-y}{2}+1}_{\frac{y}{2}}$ dy
=$\frac{1}{2}\int^4_0 [(\frac{y}{2}+1)^2-(\frac{y}{2})^2-(\frac{y}{2}+1)y+(\frac{y}{2})]$ dy
=$\frac{1}{2} \int^4_0 (y+1-y)dy $
=$\frac{1}{2} \int^4_0 dy $
=$\frac{1}{2}(4)=2$
