Making triangles
Students study the concept of triangle inequality, which determines if three positive numbers can serve as the side lengths of a triangle. This principle states that a triangle is possible if the largest of the three numbers is smaller than the sum of the other two. To explore this, students experiment with various combinations of three natural numbers. They investigate whether these numbers can form a triangle and, when they do, students classify and construct the corresponding triangle. Additionally, they learn to calculate the perimeter of these triangles.
This lesson also reviews content from Year 7 to enable students to successfully engage in four related lessons that explore the Year 8 Pythagoras' theorem content.
- Resource details
- Year level
- Year 7 Year 8
- Purpose
- Teaching resource
- Strand
- Measurement Space
- Topic
- Algorithms Area, volume and surface area Computational thinking Shapes and objects
- Audience
- Teachers
- Format
- Webpage
- Numeracy progression
- Understanding geometric properties (P4, P7) Understanding units of measurement (P8) Proportional thinking (P6)
- Publisher
- Commonwealth of Australia
- Copyright
- © 2024 Commonwealth of Australia. Creative Commons BY 4.0.
- Keywords
- congruent algorithm
- Other terms
- similarity Maths Hub lesson plan
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