Question

how to solve
(x+2y+3)(x+2y+7)​

Answer 1

Answer:

x(x+2y+7)+2y(x+2y+7)+3(x+2y+7)

x^2+2xy+7x+2xy+4y^2+14y+3x+6y+21

x^2+4xy+10x+4y^2+20y+21

Answer 2

Answer:

x²+10x+20y+4xy+4y²+21.

Step-by-step explanation:

(x+2y+3)(x+2y+7)

⇒ x(x+2y+7)+2y(x+2y+7)+3(x+2y+7)

⇒ x²+2xy+7x+2xy+4y²+14y+3x+6y+21

⇒ x²+7x+3x+14y+6y+2xy+2xy+4y²+21

⇒ x²+10x+20y+4xy+4y²+21.