Here we are given the side lengths of the triangle as 4 units (let's name this side a), 3 units (let's name this side b) and 5 units (let's name this side c).
The Pythagorean Theorem states that c^2 = a^2 + b^2.
If we were to use the values given, we will see that:
c^2 = 4^2 + 3^2
c^2 = 16 + 9 = 25
c = 5
