Question

factorise:
(L + M)² - 4LM
and explain what when and how comes please​

Answer 1

Step-by-step explanation:

(l+m) ² - 4lm

= l² + m² + 2lm -4lm {(a+b) ² = a² + b² +2 ab}

= l² + m² -2lm {(a-b) ² = a² + b² -2 ab}

= (l-m) ²