·         Example: 81x^2-16

·         I always start by rewriting my parenthesis, one set with a (+) and another with a ( - ) so it should be set up to look like (__+__)(__-__)

·         First you want to find the square root of the first part of the equation so the square root of 81x^2 is 9x which makes 81x^2 a perfect square

·         Next is to find the square root of the next part of the equation so the square root of 16 is 4 which also makes 16  a perfect square .

·         Next you will rewrite the equation as (9x+4)(9x-4)

·         Your final answer is (9x+4)(9x-4