Question

Factorise: $5x+10y-7(x+2y{)}^2.$

Answer 1

We have

$5x+10y-7(x+2y{)}^2$

$=5(x+2y)-7(x+2y{)}^2$ [Taking $5$ as common]

$=(x+2y)[5-7(x+2y\left)\right]$ [Taking $(x+2y)$ as common from both terms]

$=(x+2y)(5-7x-14y)$