Question

помогите решить
-5(x-y)-3(y+x)=
-2x(x+2y)-2y(y-x)=
-3y(-x-y)-x(2x-3y)=

Answer 1

2)...=-2x^2-4xy-2y^2+2xy=-2x^2-2xy-2y^2=-2(x^2-xy-y^2)=-2(x-y)^2
3)...=3xy+3y^2-2x^2+3xy=6xy+3y^2-2x^2