Answer:
[tex](x + y)(x + 2y) = {x}^{2} + x2y + xy + 2 {y}^{2} \\ {x}^{2} + 3x + 2 {y}^{2} \\ thank \: you[/tex]
Step-by-step explanation:
(x+y)(x+2y)
=x(x+2y)+y(x+2y)
=x^2+2xy +xy+2y^2
=x^2 + 3xy + 2y^2
