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Pythagoras' Theorem

Pythagoras' Theorem

Author: Anna Kellner

Use Pythagoras' theorem to calculate a missing side in a right angled triangle.

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This theorem is only used in right angled triangles. It can be used when you know two of the sides and you want to work out the third.


Right angle - 90o angle

Hypotenuse - the longest side in a right angled triangle, it is always opposite the right angle.

Square of a number - the number multiplied by itself

Square root of a number - the number that was multiplied by itself to get the given number as a result.

Pythagoras' Theorem video walk through

This video will show you how to solve problems involving Pythagoras' Theorem.