Similar Figures Definition: a plain-English explanation of what the term means, why it matters in math, and how it is used, followed by worked examples and practice questions so the definition turns into something you can apply.
Math Dictionary / Similar Figures
Similar Figures
Similar figures have the same shape but not necessarily the same size.
GeometryGrade 7Grade 8Algebra 1SATACT
What it means
Corresponding angles match, and corresponding side lengths are proportional.
Also called: same shape
Examples
| Two triangles can be similar if all angle measures match |
| A scale drawing is similar to the real object |
| Side lengths may double while angles stay equal |
Common mistake
Similar does not mean equal size. That is congruent.
Try one
Question: If a figure is enlarged by a scale factor of 3, is it similar to the original?
Show answer
Yes. A dilation creates a similar figure.