因式分解，会的帮帮我

（x+y）^2-4(x^2-y^2)+4(x+y)^2
=5(x+y)^2-4(x+y)(x-y)
=(x+y)[5x+5y-4x+4y]
=(x+y)(x+9y)

（x+y）^2-4(x^2-y^2)+4(x+y)^2

=5(x+y)^2-4(x^2-y^2)

=5x^2+10xy+5y^2-4x^2+4y^2

=x^2+10xy+9y^2

=(x+9y)(x+y)

（x+y）^2-4(x^2-y^2)+4(x+y)^2
52-4(X+Y)(x-y)
（x+y）[5（x+y）-4(x-y)]
（x+y）(5x+5y-4x+4y)
(x+y)(x+9y)

上式=5(X+Y)^2-4(x^2-y^2)
=(X+Y)[5(X+Y)-4(X-Y)]
=(X+Y)(X+9Y)

（x+y）^2-4(x^2-y^2)+4(x+y)^2=x^2+10xy+9y^2=(x+y)(x+9y)

x^2+9y^2+10xy