This is another video in the Year 9 series looking at Pythagoras' Theorem and Trigonometry. Having already built the basics, I am now going to look at how we can apply Pythagoras' Theorem to three dimensional (3D) shapes. All you need to know is how to find a right angled triangle. Once you have identified it, you can mark the two sides you know and find the one you don't. I look at a number of common examples including a hemisphere (which I have seen used over and over again!) as well as explain that you might need to do more than one calculation in order to get the side length you need. As always, the explanations are clear and easy to understand and designed to help you smash maths.