Question

simplify 9a^2 - 4(a-b)^2

Answer 1

it looks like a difference of squares x^2 - y^2 where

x = 3a
y = 2(a-b)

good luck :)

Answer 2

(a+b)(a-b) = a^2 - b^2

Answer 3

9a^2 - 4(a-b)^2
9a^2 - 4(a^2+b^2-2ab)
9a^2 - 4a^2-4b^2+8ab
5a^2-4b^2+8ab