The formula that relates the lengths of the sides of any right triangle: 
, where c is the hypotenuse, and a and b are the legs of the right triangle.
| hypotenuse | The side opposite the right angle in any right triangle. The hypotenuse is the longest side of any right triangle. |
| leg | In a right triangle, one of the two sides creating a right angle. |
| Pythagoras | A Greek philosopher and mathematician who lived in the 6th Century B.C. |
| Pythagorean Theorem | The formula that relates the lengths of the sides of any right triangle: |
| right triangle | A triangle containing a right angle. |