Unit 7 Lesson 4 Polygons

Unit 7 Lesson 4: Polygons 

Unit 7 Lesson 4: Polygons

Lesson Overview

Polygons

 

What You Will Learn

What You Will Learn
  • to find the interior and exterior angles of a polygon

Overview

In this lesson, you will learn to find the sum of a polygon's exterior and interior angles by a formula. In this textbook, a polygon is convex unless otherwise stated.

  • Read Pages 199-205 in your course textbook

Essential Understanding

The sum of the interior angle measures of a polygon depends on the number of sides the polygon has. By dividing a polygon with n sides into (n - 2) triangles, you can show that the sum of the interior angle measures of any polygon is a multiple of 180.

 

Lesson 4: Polygons

Proceed to the Next Page

Prepare for Application 

Instructions

Prepare for Application

You have now studied Polygons. It is now time to demonstrate your learning.

Try the activities below on your own. You should be able to answer these before beginning the practice.

 

Create an extra journal called 'Unit 7: Lesson 4 activities' and do these in your journal.

 

Activity 1
  1. What is the sum of the interior angle measures of a 17-gon?
  2. The sum of the interior angle measures of a polygon is 1980. How can you find the number of sides in the polygon?
Activity 2

What is the measure of each interior angle in a regular nonagon?

Activity 3

What is mG in quadrilateral EFGH shown below?

Activity 3

Activity 4

What is the measure of an exterior angle of a regular nonagon?