Question

How do you factor `8x² − 72`?

Answer 1

`8(x^2-3^2)=8(x+3(x-3)`

Answer 2

`8(x+3)(x-3)`

Explanation:

First, we can facter `8` out of the expression as the two terms are multiples of `8`.

`8x^2-72=8(x^2-9)`

Now in the brackets we see that we have the difference of 2 squares, (`x^2 = (x)^2`and `9 = 3^2`) so we can further factorise to:

`8(x+3)(x-3)`

And we're done.