Question

How do you factor `9x^2 - 16`?

Answer 1

`color(blue)(a^2 - b^2 = (a+b)(a-b)`

`9x^2 - 16 = (3x)^2 - (4)^2`

`(3x)^2 - (4)^2 = color(red)((3x-4)(3x+4)`