Answer:
third side = 3
Explanation:
using Pythagoras' identity in the right triangle.
the square on the hypotenuse is equal to the sum of the squares on the other 2 sides.
let the third side be x , then
x² + 4² = 5²
x² + 16 = 25 ( subtract 16 from both sides )
x² = 9 ( take square root of both sides )
x =
= 3