K-5 friendly lesson
One small step at a time.Read the idea, try the activity, and celebrate each win as you go.
Regular and Irregular Polygons
A regular polygon has all sides and all angles equal. Irregular polygons do not.
Do this: Read the concept below, then try the quiz or activity.
Lesson 206 of 216
Concept
Polygon = closed figure with straight sides.
Regular polygon: - equal side lengths - equal angle measures Examples: regular triangle, square, regular pentagon.
Irregular polygon: - at least one side or angle differs.
Use side length and angle clues to classify shapes correctly.
Try it
Classify each as regular or irregular: 1. Triangle with sides 5,5,5 2. Rectangle 4 by 7 3. Pentagon with all equal sides and angles 4. Quadrilateral with sides 3,3,5,5 5. Draw one regular and one irregular polygon.