Question

(x+13)(x+20 ) use identityies

Answer 1

$\color{purple} \mathcal{ \colorbox{orange}{\colorbox{white}{Identity~→~(x+a)~(x+b)~=~x²~+~xa~+~xb~+~ab}}}$

$\rm{\dashrightarrow (x~+~13)~(x~+~20)}$

$\rm{\dashrightarrow x²~+~(13x)~+~(20x)~(13~×~20)}$

$\rm{\dashrightarrow x²~+~13x~+~20x~+~260}$

$\rm{\dashrightarrow x²~+~33x~+~260}$

${\sf\bold{Hope~it~helps~:)}}$