Pythagoras in 3D

MathematicsAQAEdexcelGCSEUnit: Geometry & Measures
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The basics

From Flat to 3D

From Flat to 3D

Ever wondered how to find the diagonal of a box, or the space diagonal of a room? Use Pythagoras TWICE! First find the diagonal of the base (2D), then use that as one side of a new right triangle going up (3D). It's the same a² + b² = c² logic, just used in layers.

Now try it yourself

Quiz · Question 1 of 12

A cuboid has length l, width w, and height h. Which formula gives the length of the space diagonal d?

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