So say you have a triangle and you know two of the legs but not the hypotenuse and one of the legs is 4 and the other is 5. What you would do is set it up as 42 +52=x2. Then you square 4 and 5 and get 41=x2. Then you take the square root of both sides and have the square root of x2= square root of 41. Then you have x=sqr. root of 41 and that is they hypotenuse. It is either that or 6.4 if you have to go to the nearest tenth.
