Key learning points

1. Exterior angles of a regular polygon are equal.
2. The size of the exterior angle of a regular polygon can be determined.
3. Interior angles of regular polygons are equal.
4. The size of the interior angle of a regular polygon can be determined.
5. The number of sides in a regular polygon can be determined from the size of the interior or exterior angle.

Common misconception

Keywords

• Polygon - A polygon is a flat (2D), closed figure made up of straight line segments.

• Regular polygon - A regular polygon has sides that are equal and interior (inside) angles that are all equal.

• Interior angle - An interior angle is an angle formed inside a polygon by two of its edges.

• Exterior angle - An exterior angle is an angle on the outside of a polygon between an extension of an edge and its adjacent edge.