Pythagoras' Theorem: From Right Triangles to 3D Diagonals
Shared by A STEM Educator★ Featured Teacher · rated 90+ in our quality review
Students will be able to apply Pythagoras' theorem to find unknown side lengths in right-angled triangles in both 2D and 3D contexts, including composite and real-world problems.
Lesson Overview
Students progress from identifying and labelling sides of a right triangle through to applying Pythagoras' theorem in 3D contexts, changing only one variable at a time across seven carefully sequenced tasks on vertical whiteboards.
Materials
- Vertical whiteboards or large chart paper
- Dry-erase markers (multiple colours)
- Pencils and paper for notes
- Basic calculator (phone calculator is fine)
Scaffolded Task Progression
[ Interactive graph / diagram, available in the full lesson ]
1. Label which side is the hypotenuse and explain how you know.
2. Calculate the length of .
[ Interactive graph / diagram, available in the full lesson ]
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