(5х +7y)*(9х +11 y)-(2х +5y)(в квадрате)

Question

(5х +7y)*(9х +11 y)-(2х +5y)(в квадрате)

Answer 1

(45х^2 + 63xy+55xy+77y^2) - (4x^2+ 20xy+25y^2) = 45x^2+118xy+77y^2-4x^2-20xy+25y^2 =

 = 41 x^2+98xy+102y^2