# Similar Polygons

Two polygons are similar if and only if their corresponding angles are congruent and the measures of their corresponding sides are proportional.

In congruent figures, corresponding angles and sides are congruent. In similar figures, corresponding angles are congruent, and the measures of the corresponding sides have equivalent ratios, or are proportional.

To determine if polygons are **similar**, you must do two things:

(1) Verify that corresponding angles are congruent

(2) Verify that corresponding sides are proportional.

**Scale drawings **are often used to represent something that is too large or too small to be drawn at actual size. Contractors use scale drawings called *blueprints *to represent the floor plan of a house to be constructed. The blueprint and the floor plan are similar.

**Scale factor: **The ratio of the lengths of two corresponding sides of similar polygons.

Read the explanation below to learn more about similar polygons.

**Practice:** Answer the exercises below by identifying similar polygons.