Question

Multiply: (9x + 6)(9x - 6).

Answer 1

81x^2 -36

Answer 2

81^2 -54x+54x- 36 on expansion.

Answer 3

(9x)^2-6^2
81x^2-36

Answer 4

Thank You

Answer 5

Note that "order" answer when simplified is the same as the others.

Answer 6

the -54x+54x sort of eliminate each other. The difference of two perfect squares is something you should memorize its factors: \[a ^{2}-b ^{2}=(a+b)(a-b)\]