Question

How do you factor `9x^2 - 4`?

Answer 1

`(3x-2)(3x+2)`

Explanation:

`a^2-b^2=(a-b)(a+b)`
let `a^2=9x^2, and b^2=4`
`a=3x, b=2`
`9x^2-4=(3x-2)(3x+2)`