Question

Разложите на множители:
4x-x^2+y^2-4y.
Помогите, прошуууууу...

Answer 1

4x-x²+y²-4x=(4x-4y)-(x²-y²)=4(x-y)-(x-y)*(x+y)=(x-y)*(4-(x+y)))=(x-y)*(4-x-y).