Question

Помогите пожалуйста срочно

Answer 1

$frac{a^2+y^2}{ay-y^2} - frac{2a}{a-y} = frac{a^2+y^2}{y(a-y)}- frac{2a}{a-y}= frac{a^2+y^2}{y(a-y)} - frac{2ay}{y(a-y)}= frac{a^2+y^2-2ay}{y(a-y)}= frac{(a-y)^2}{y(a-y)}$
$=frac{a-y}{y}$