The Geometer´s warehouse

 

Back to home

Exterior angle of a convex polygon

Investigate the sum of the exterior angles of a polygon by clicking and dragging any of the blue points.

1. What observation can you make regarding the sum of the exterior angles of a polygon?
2. What relationship exists between any exterior angle and its adjacent interior angle?
3. In a polygon with n sides, the sum of all interior angles and their adjacent exterior angles is n x 180°. The interior angle sum of a polygon with n sides is equal to (n - 2) x 180°. Using these two results, confirm you answer to question (1).

© State of New South Wales, Department of Education, 2018