Angles in Polygons

A polygon is a closed plane figure formed by three or more segments. A polygon is named by the number of its sides

Find the sum of the angle measures in a polygon by dividing the polygon into triangles

The angle measures of a triangle add up to 180° (Triangle Sum Theorem)

An n-gon (a polygon having n sides) can be divided into n - 2 triangles. The sum of the angle measures of any n-gon (a polygon having n sides) is 180° (n - 2)

If all sides and angles of a polygon are congruent, the polygon is known as a regular polygon