This section will explain how to use The Pythagorean Theorem to find a missing hypotenuse. If we are given a triangle's legs, then we would use the equation to calculate the length of the hypotenuse. Say we know the shortest sides to be 3 m and 7 m. The example below outlines the process by which we can calculate the hypotenuse.

1. The equation is written. This will allow us to organize our information and process it accordingly.
2. The values for 'a' and 'b' are placed within the equation, since they represent the lengths of the shortest sides.
3. Order of operations dictates that the values should be squared before they are added. 3 x 3 = 9 and 7 x 7 = 49.
4. The sum of 9 and 49 is 58, or 9 + 49 = 58.
5. To cancel the square of c, the right side of the equation, we must take the square root of both sides. The square root of a square of a value is equal to the original value. If we must take the square root of the right side, the same must be done to the left side.
6. The square root of 58 is 7.6157. Only four decimal places of an infinitely long, non-repeating answer has been displayed.
7. The final answer has been rounded to the hundredths place. Since the thousandths place was five or greater, the hundredths place was increased by 1.