This lesson can be used for revision for the higher Maths GCSE. The examples are quick and concise with exam style questions, go to GCSE Maths if you need more in-depth explanations.

How and when to use the Phythagoras Theorem

When to use Pythagoras Theorem?

- You are given a right angled triangle

- You are given two sides and asked to find the third sides

- The figure is not drawn to scale

There are two cases:

Case 1:

Find the longest side. (The longest side is the side opposite the right angle)

Case 2:

Find the shorter side.

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