1. Module 5

1.6. Lesson 2

Mathematics 10-3 Module 5 Lesson 2

Module 5: Angles

 

Lesson 2: Constructing Congruent Angles

 

Focus

 

This is a photograph of a star quilt with a First Nations design.

© Alice Day/shutterstock

Lakota star quilts remind people that art and design play an important role in the lives of First Nations people of the prairies and plains. This design represents the Morning Star and signifies a fresh start to a person’s life. Blankets and quilts, such as the one in the photograph, are given as gifts to celebrate births, weddings, and other milestones.

 

The pattern incorporates the repetition of angles and geometric shapes. If you examine the star closely, you can see how carefully identical—that is, congruent—geometric figures are stitched together to create a star. In the star you can see congruent parallelograms, triangles, rectangles, and trapezoids. How many sets of congruent angles can you find?

 

Lesson Questions

 

In this lesson you will explore the following questions:

  • How are congruent angles defined?
  • How are congruent angles constructed?
Assessment

 

You will complete the Lesson 2 Assignment Booklet for assessment. Download the Lesson 2 Assignment Booklet and save it in your course folder now. You will receive instructions on how to complete the Assignment Booklet later in the lesson. You will also be prompted to start working on the Unit 3 Project.

 

Remember to save all activities, including those that are not part of the Assignment, in your course folder.

 

Required Materials and Equipment

 

For this lesson you will need

  • a protractor
  • a compass
  • a square from a geometry set
  • several blank sheets of paper
  • a straightedge or ruler