Key learning points

1. Missing angles can be found in polygons using knowledge of exterior and interior angles.
2. A missing angle can be represented with an unknown.
3. Algebraic statements can be written about the missing angles in polygons.

Keywords

• 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 the adjacent edge.

Common misconception