Unit 8, Lesson 5-- Convex and Concave Polygons

Lesson 5-- Convex and Concave Polygons

Introduction

Hello Mathematicians! You have learned about the different kinds of polygons, as classified by their number of sides.  Today, you will learn about convex and concave polygons.


Video


Interactive

Part 1 Directions:

  • Practice identifying and sorting convex and concave shapes.

Part 2 Directions:

  • Use the geoboard to create convex and concave shapes. (Use the square geoboard.)
  • Draw 2 of each in your math notebook, and label the angles as convex or concave.


In Your Math Notebook

Let’s get out our math notebook and  work through the following application problem. Make sure you read the problem carefully, draw a picture to match your thinking and write an answer with numbers and words.

Read, Draw, Write. DONE!

R (Read the problem carefully.)

Mr. Summers’ class was building shapes with toothpicks. He challenged the class to build a concave shape.  Emily lost all but 3 of her toothpicks, and said “Mr. Summers, this isn’t possible!” Is she right?  Why or why not?

D (Draw a picture.)

W (Write an answer with numbers and words.)

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