How do you find the missing length of a right triangle, when the two sides given are in radical form?

Well, I'm having trouble with a Geometry question. So it basically has a right triangle, and the hypotenuse and the leg opposite from the hypotenuse are given: hypotenuse = √15ft leg opposite from hypotenuse = √14ft Now, I know you have to use the Pythagorean theorem, but how do you do use it in a situation like this? *Thanks for help!*