How do you find the slant height of a triangular prism?

use the Pythagorean therom ... C2=A2+B2 draw a little triangle name your sides and use the therom to solve for the hypotenuse which is c.......

This means that your slant would be the hypotenuse in the therom thus the square root of c is equal to the square root of side a plus the square root of side be it's best just to use a scientific calculator