1. Holt Geometry 6-1 Properties and Attributes of Polygons 6-1 Properties and Attributes of Polygons Holt Geometry Warm Up Warm Up Lesson Presentation Lesson Presentation Lesson Quiz Lesson Quiz

2. Holt Geometry 6-1 Properties and Attributes of Polygons Find and use the measures of exterior angles of polygons. Objectives

3. Holt Geometry 6-1 Properties and Attributes of Polygons An exterior angle is formed by one side of a polygon and the extension of a consecutive side. Remember!

4. Holt Geometry 6-1 Properties and Attributes of Polygons Note 43

5. Holt Geometry 6-1 Properties and Attributes of Polygons Example 4A: Finding Interior Angle Measures and Sums in Polygons Find the measure of each exterior angle of a regular 20-gon.

6. Holt Geometry 6-1 Properties and Attributes of Polygons Example 4B: Finding Interior Angle Measures and Sums in Polygons Find the value of b in polygon FGHJKL.

7. Holt Geometry 6-1 Properties and Attributes of Polygons Find the measure of each exterior angle of a regular dodecagon. Check It Out! Example 4a

8. Holt Geometry 6-1 Properties and Attributes of Polygons Check It Out! Example 4b Find the value of r in polygon JKLM.

9. Holt Geometry 6-1 Properties and Attributes of Polygons 1. Name the polygon by the number of its sides. Then tell whether the polygon is regular or irregular, concave or convex. 2. Find the sum of the interior angle measures of a convex 11-gon. Lesson Quiz nonagon; irregular; concave 1620° 3. Find the measure of each interior angle of a regular 18-gon. 4. Find the measure of each exterior angle of a regular 15-gon. 160° 24°