Algebra 1 · Factoring

Greatest Common Factor

Algebra 1 · Factoring

Definition

The greatest common factor is the largest factor shared by all terms of an expression.

Examples

  • The GCF of 12x and 18 is 6.
  • The GCF of 4x^2 and 6x is 2x.

Key rule

Factor out the GCF before any other factoring.

Memory hook

GCF = the biggest piece every term shares.