Question

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

Answer 1

A very slightly different way of presenting the calculation:

`" "(3x-4)(3x+4)`

Explanation:

Write as:`" "3^2x^2-4^2`

Which is the same as:`" "(3x)^2-4^2`

It is known that standard form of `a^2-b^2=(a+b)(a-b)`

So we have:`" "(3x-4)(3x+4)`