Geometry · Similarity & Right Triangles

Scale Factor

HSG-SRT.A.2

Definition

The ratio of corresponding lengths in similar figures, used to enlarge or reduce.

Examples

  • If a figure's sides double, the scale factor is 2.
  • A scale factor of 1/2 shrinks a figure to half its original size.

Key rule

A scale factor greater than 1 enlarges; less than 1 reduces.

Memory hook

The multiplier that resizes similar figures.