1. 9.4 - Polygons
Grade 4

2. Polygons
You have learned the special names for different types of lines and angles. Today, you will learn the special names for different types of polygons.
What are some flat objects in the classroom that have only straight sides?
Watch video on Polygons

3. Vocabulary Polygon – A closed flat shape with straight sides.
Vertex – When 2 sides of a polygon meet at a point. (Plural – vertices)
Triangle – 3 sides
Quadrilateral – 4 sides
Pentagon – 5 sides
Hexagon – 6 sides
Octagon – 8 sides
(notes should have been taken from the video)

4. Not Polygons
Why are these NOT polygons?

5. Practice
Name each polygon if possible. What is the number of SIDES and Vertices it has?

6. Practice - Answers
Name each polygon if possible. What is the number of SIDES and VERTICES it has?
10 sided polygon; sides, 10 vertices
Triangle 3 sides; 3 vertices
7-sided polygon 7 sides, 7 vertices

7. Homework
Pg. 202 (#1 – 20)