Question

How do you factor `9b^2-36`?

Answer 1

`9b^2 - 36` can be written as `(3b)^2 - (6)^2`

this is of the form:

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

here: `a = 3b` and `b = 6`

so ,

`(3b)^2 - (6)^2= (3b +6) (3b - 6)`

the factorized form of `9b^2 - 36` is:

`(3b +6) (3b - 6)`