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
- x^2 + 6x + 9 = (x + 3)^2.
- x^2 - 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.