Question

How do you factor `4x^2 - 64y^2`?

Answer 1

`4x^2 -64 y^2=color(blue)((2x+8y)(2x-8y)`

Explanation:

`4x^2 - 64y^2` is of the form `color(blue)(a^2 - b^2` (where `a=2x , b=8y)` , and as per the identity:
`color(blue)(a^2 - b^2= (a+b)(a-b)`

So, `4x^2 -64 y^2=color(blue)((2x+8y)(2x-8y)`