Question

(x+y) (2x+y)+(x+2y) (x-y) -(x+y)-(x+y)​

Answer 1

Step-by-step explanation:

(x+y)(2x+y)+(x+2y)(x−y)

=x(2x+y)+y(2x+y)+x(x−y)+2y(x−y)

=2x2+xy+2xy+y2+x2−xy+2xy−2y2

=(2+1)x2+(1+2−1+2)xy+(1−2)y2

=3x2+4xy−y2