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Four Points on a Cube

Stage: 5 Challenge Level: Challenge Level:1
Why do this problem?
It gives experience of using 3D coordinates, visualisation, and using the distance formula in 3D, and formulae for the area of a triangle.

Possible approach
A good diagram isessential. You might discuss and draw and label the diagram as a class effort and then the students could complete the calculatons independently.

Key questions
What are the coordinates of the vertices of the tetrahedron?