The hypotenuse of a 45°-45°-90° triangle measures 18 cm. what is the length of one leg of the triangle?

Since one of the angles is 45 degrees, we can set up an equation to find the length of one of the legs.
sin45 = x / 18
x = 18sin45
x = 12.727 cm

Or you can just do 18 / √2 = 12.727
This is because 45-45-90 triangle for the sides is a, a, a√2. Hypotenuse is a√2 so that’s why we solved it as a√2 = 18 where
a = 12.727