A polygon is a closed-sided figure with 3 or more sides.
Types of Polygons
Classification of Triangles and Quadrilaterals
Using hatch marks and angles to illustrate Triangles
Using a Table to Highlight the Types of Triangles
Said in a different way...
How many triangles are in the following illustration ...
What is similar and different about the following polygons?
Using Charts to Classify Quadrilaterals
Using a Tree Diagram
Words and Pictures
Classifying Shapes by Lines and Angles