Mathematics
OpenStudy (anonymous):

$\Large \frac{8y^2 - 10xy}{4y}$ $\Large \frac{2y(4y - 5x)}{4y}$ $\Large \frac{2y(4y - 5x)}{2*2y}$ $\Large \frac{\cancel{2y}(4y - 5x)}{2*\cancel{2y}}$ $\Large \frac{4y - 5x}{2}$ So $\Large \frac{8y^2 - 10xy}{4y} = \frac{4y - 5x}{2}$