Geometry · Quadrilaterals & Polygons
Exterior Angle Sum
HSG-CO.C.11
Definition
The exterior angles of any convex polygon total 360 degrees.
Examples
- One exterior angle per vertex, and they always sum to 360 degrees, no matter how many sides.
- A regular hexagon's six exterior angles are each 60 degrees, summing to 360 degrees.
Key rule
Exterior angle sum is always 360 degrees, regardless of the number of sides.
Memory hook
Always 360 degrees — no matter how many sides.