Question

Factor the following terms9x^2-81

Answer 1

The given expression:

`9x^2-81`

The expression can be written as :

`9x^2-81=9x^2-9*9`

Take 9 common :

`9x^2-81=9(x^2-9)`

Since 3 x 3 = 9

`9x^2-81=9(x^2-3^2)`

Apply the property of factorization:

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

So, the expression can be written as :

`9x^2-81=9(x-3)(x+3)`

So, the factorization is : 9(x + 3) (x - 3)

Answer :

`9x^2-81=9(x-3)(x+3)`