# Polygons Exterior Angle sum

- Author:
- rikeylee

- Topic:
- Polygons

What is the sum of the exterior angles of a n-gon?
Use the following sketches to investigate. See if you can come up with a formula (like we did for the sum of the interior angles of an n-gon) that if you put the number of sides in for n, it gives you the sum of the exterior angles for that polygon.
Be sure to drag the polygon around so that you confirm that the formula works for any polygon with that number of sides, not just the one that you see when you first click on the tab.
Like we did for the sum of the interior angles, try to explain why the formula that you discovered for the question above works.