Question

pls solve question no. 2

Answer 1

the simplified form is 84xy

Answer 2

(ii)(3x+7y)²-(3x-7y)²
This is in the form of (a+b)²-(a-b)²
(a+b)²-(a-b)²=4ab
4ab=4×3x×7y
so the answer is 84xy