Pythagoras' Theorem

Pythagoras was a Greek philosopher who discovered that in a right angled triangle (triangle with one angle 90 degrees) the hypotenuse squared , c2, was equal to the sum of the other sides squared, a and b. The hypotenuse is the longest edge and is opposite the right angle, a and b are the adjacent sides, next too, the right angle. 

We call this Pythagoras' Theorem: a2+b2=c2

If we know two of the three sides we can use this theorem to work out the other, by subbing in the values known and rearranging.

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