Algebra: Triangle Inequality

This is a classic reSolve sequence aligned with the Australian Curriculum V8.4. It is only available as a downloadable package.

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Students discover an important property about triangles while exploring the concepts of equality and inequality.

This task is for students who:

• understand a triangle as a polygon (i.e. a closed, plane shape, with three straight sides and three corners), and are familiar with non-equilateral triangles.
• can identify and represent equality using the equals sign.
• are comfortable using the is greater than (>) and is less than (<) symbols.

 

Lesson 1: Triangle Inequality

This task explores the triangle inequality theorem. Students use 20 matchsticks to create different triangles. Using 20 sticks, it is possible to make only eight different triangles. Students will learn that, in any triangle, the sum of the lengths of any two sides must be greater than the length of the third side. They are asked to represent inequalities using the is greater than and is less than symbols.

 

Last updated June 15 2020.

This is a classic reSolve sequence aligned with the Australian Curriculum V8.4. It is only available as a downloadable package.

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