Pythagoras' Theorem

MathematicsAQAEdexcelGCSEUnit: Geometry & Measures
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The basics

The Ancient Discovery

The Ancient Discovery

Over 2,500 years ago, Pythagoras discovered a beautiful relationship in right-angled triangles: if you square the two shorter sides and add them together, you get the square of the longest side (the hypotenuse). This works for EVERY right-angled triangle in the universe!

Visual: Pythagoras' Theorem

Diagram showing Pythagoras theorem with squares on each side of a right triangle. a² + b² = c² where c is the hypotenuse. Includes formulas for finding hypotenuse and shorter sides.
Spotlight
The Formula

Where c is the hypotenuse (the longest side, opposite the right angle)

Now try it yourself

Quiz · Question 1 of 17

In a right-angled triangle with legs a and b and hypotenuse c, which formula is Pythagoras' theorem?

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