## Exterior Angles

**Work Time**

# Exterior Angles

Look at the exterior angle measurements for each polygon.

- Draw a pentagon, a hexagon, and an octagon. What do you think the sum of the exterior angles will be on each polygon? Measure each angle and check.
- What do you notice about the exterior angle sum for each polygon? Do you think this will be true for all polygons?
- Looking at the angles mathematically, what is the sum of the measures of exterior angles in terms of the interior angles?

For example, if the quadrilateral angles are labeled*a*,*b*,*c*, and*d*, the exterior angles are $(180\xb0-a)$, $(180\xb0-b)$, $(180\xb0-c)$, $(180\xb0-d)$. What is the sum of the measures of angles*a*,*b*,*c*, and*d*? - What can you conclude about the sum of exterior angle measures in polygons?

HANDOUT: Exterior Angles of Polygons