what's the difference of two squares
The result from the last problem is called a Difference Between Two Squares. A Difference Between Two Squares is an expression with two terms (also known as a binomial) in which both terms are perfect squares and one of the two terms is negative. The pages that follow show how to factor a difference between two squares. The factoring process, which converts an expression like x 2 - 4 into (x - 2)(x + 2), is essentially the opposite of the multiplication process we used above.