Question

factorise - (l+m)²-4lm

Answer 1

(l+m)^2 - 4lm

=> l^2 +m^2 +2lm - 4lm

=> l^2 +m^2 - 2lm

=> l^2 + m^2 - 2(l)(m)

=> (l-m) ^2

Answer 2

Answer:

The factorized form of given expression is $(l-m)^2$.

Step-by-step explanation:

The given expression is

$(l+m)^2-4lm$

Simplify the given expression by using perfect square formula.

$l^2+2lm+m^2-4lm$               $[\because (a+b)^2=a^2+2ab+b^2]$

Combine like terms.

$l^2+(2lm-4lm)+m^2$

$l^2-2lm+m^2$

$(l-m)^2$               $[\because (a-b)^2=a^2-2ab+b^2]$

Therefore the factorized form of given expression is $(l-m)^2$.