Shapes with flat, angled sides, like pyramids, work best to create 3D shadows. Once you've made your selections, take your flattened cardboard box and start tracing triangles (or the shape of your ...

Pythagoras' theorem can also be used to solve 3D problems. You often need to use Pythagoras' theorem more than once in each problem as we create extra right-angled triangles in the 3D shapes.