Answer:
-y^2
Step-by-step explanation:
x(x-2y)-(y-x)^2=
Distribute
x^2 -2xy -(y-x)^2=
Foil
x^2 -2xy -(y^2 -2xy+x^2)=
Distribute the minus sign
x^2 -2xy -y^2 +2xy-x^2=
Combine like terms
