Answer:
10
Explanation:
Let x represent the third side
This is a right triangle
In right triangle the sum of square value of both legs is equal to square value of hypotenuse(the third side in this case)
Let x represent the third side
5^2 + 5
^2 = x^2
25 + 75 = x^2
100 = x^2 find the root for both sides
10 = x