Use the concept of the Pythagorean Theorem, where the sum of the squares of legs 1 and 2 is equal to the square of the hypotenuse. This means you can take the square root of the hypotenuse square and obtain its length since a square’s area is s².
So, here’s the equation:
t²+s²=u²
Where t=leg 1, s=leg 3, and u=hypotenuse