Algebra 1 · Factoring
Difference of Squares
Algebra 1 · Factoring
Definition
A difference of squares is a binomial a2 − b2 that factors as (a + b)(a − b).
Examples
- x2 − 16 = (x + 4)(x − 4).
- x2 − 25 = (x + 5)(x − 5).
Key rule
Factor a2 − b2 into conjugate binomials.
Memory hook
Difference of squares splits into plus and minus twins.