Solve $\frac{dy}{dx}=\frac{x^2-xy-y^2}{x-y}$

Question

This is what i did: \begin{align} \frac{dy}{dx}& =\frac{x^2-xy-y^2}{x-y}\\ \frac{dy}{dx}& =\frac{(x+y)(x-y)-xy}{x-y}\\ \frac{dy}{dx}& =x+y-\frac{xy}{x-y} \end{align} I put $z=\frac{y}{x-y}$, is this solution alright? I could not just go on, because the equation is neither Bernoulli or exact or homogenous.