Lesson 5

1. Lesson 5

Mathematics 20-3 Module 4

Module 4: The Right Kind Of Triangles

 

Lesson 5: Solving Problems Involving Two or More Right Triangles in Three Dimensions

 

Focus

 

This is an image of a pyramid constructed from coloured triangular pieces.

© pzAxe/10589384/Fotolia


 

This three-dimensional pyramid took knowledge of trigonometry and the Pythagorean theorem to create. Can you see where the right triangles exist in this puzzle? They are not obvious because they are hidden inside the triangle. At what angle must the puzzle pieces be cut so that they fit together at the edges where the faces meet?

 

In Lesson 5 you will see other problems similar to this, where two or more right triangles will be needed to help find the solution.

 

In this lesson you will use your understanding of right triangles to solve problems involving two or more right triangles in three dimensions.

 

Lesson Question

 

In this lesson you will investigate the following question:

  • How are three-dimensional problems solved using two or more right triangles?
Assessment

 

Your assessment for this lesson may include a combination of the following:

  • course folder submissions from Try This and Share

  • Lesson 5 Assignment (Save a copy of your lesson assignment to your course folder now.)

  • the Project Connection
Materials and Equipment
  • calculator
  • tape measure or ruler
  • protractor
  • small open box, such as a shoe box
  • stiff paper or cardstock (e.g., an old file folder)
  • scissors
  • markers
  • a thin, straight rod about 40 cm long