Algebra 1 · Factoring
Perfect Square Trinomial
Algebra 1 · Factoring
Definition
A perfect square trinomial is a trinomial that factors as a binomial squared, (a + b)2.
Examples
- x2 + 6x + 9 = (x + 3)2.
- x2 − 10x + 25 = (x − 5)2.
Key rule
The first and last terms are perfect squares; the middle is twice their roots.
Memory hook
Perfect square trinomial = a binomial squared.