1. Go over quiz

2. 3.4 Polygon Angle Sum Theorems
10/28 with practice on 10/29

3. Learning Targets
I can name and classify a polygon given the number of sides and vertices.
I can find the interior angles of a polygon using the Polygon Angle Sum Theorem
I can find the exterior angle of a polygon using the Polygon Exterior Angle Sum Theorem

4. Polygon : a polygon is a closed plane figure with at least three sides that are segments. The sides intersect only at their endpoints.

6. To name a polygon, you must name the vertices consecutively
EX:

7. Convex polygon: Has no diagonals with points outside the polygon.
Concave polygon: Has at least one diagonal with points outside the polygon. EX

8. Part a is Convex part b is Concave

9. Polygon Classification
3 sides-
4 sides-
5 sides-
6 sides-

10. Polygon Classification(cont’d)
7 sides -
8 sides -
9 sides -
10 sides -
12 sides -
N sides -

11. Polygon Angle Sum Theorem: The sum of the measures of the interior angles of any polygon is (n – 2)180, where n is the number of sides.

12. Ex.
What is the sum of the measures of angles of a
Decagon?
Pentagon?

13. Find the sum of the measures of angles of an octagon
In your groups
Find the sum of the measures of angles of an octagon

14. Find x

15. In your groups
The sum of the measures of the interior angles is How many sides does it have?
Hint: Work backwards

16. Polygon Exterior Angle Sum Theorem: The sum of the exterior angles of a polygon is 360 degrees. ALWAYS!

17. The following is SUPER IMPORTANT!!!
An Equilateral polygon has all sides congruent.
An Equiangular polygon has all angles congruent.
The following is SUPER IMPORTANT!!!
A regular polygon has all equal angles and equal sides.

18. In your groups
What is the measure of an exterior angle of a regular hexagon?
What is the measure of an interior angle of a regular dodecagon?

19. In your groups
The following is a regular polygon, find the missing measures

20. In a regular polygon, the sum of an interior angle and exterior angle is 180°

21. Homework
In packet 3-4

22. Day 2 for 3.4 Warmup – Grab your book For a regular nonagon
What is the measure of an interior angle?
What is the measure on an exterior angle?

23. Go over 3-4 Packet.

24. P.147 #16-21

25. 3-4 worksheet practice