Question

Is this correct ?
Factor: 9x2 - 64
(9x + 8)(x - 8)

Answer 1

nope...difference of 2 squares is a^2 - b^2 = (a+b)(a-b)
in your case, a=3x, b=8

Answer 2

so (3x - 8)(3x - 8)

Answer 3

nope... one is +, one is -

Answer 4

3x + 8)(3x - 8)

Answer 5

yes

Answer 6

Think of yours as (3x) ^2 - 8^2 --> difference of two squares.

Follow the pattern: (3x + 8) (3x - 8)