# Exterior Angles Investigation

Topic:
Angles

## Objective

Your learning objective is to discover the relationship between the exterior angles of a polygon and develop a way to extend your understanding to all regular polygons.

## 1.

What seems to be true about a triangle's exterior angles? Describe what you see.

## 2.

Suppose the blue angle measures 130 degrees and the pink angle measures 150 degrees. Predict what the measure of the purple angle be?

Note: For the polygons that follow (quadrilateral, pentagon, hexagon), these applets will work best if the polygon is kept CONVEX. If you don't remember what this term means, click here for a refresher.

## 3.

What seems to be true about a quadrilateral's exterior angles? Describe what you see.

## 4.

Suppose the blue angle measures 110 degrees and the pink angle measures 120 degrees and the green angle measures 60 degrees. What will the measure of the purple angle be?

## 5.

What can we conclude about a pentagon's 5 exterior angles? What can we conclude about a hexagon's 6 exterior angles? Describe the phenomena you observed.

## Quick Demo. BGM: Andy Meyers

Consider the regular pentagon below. Use the diagram to look at this relationship.