Answer:
6
Step-by-step explanation:
From the pythagorean theorem the square lenght of hypotenuse is equal to sum of square lenght of base and side
(6.5)^2 = x^2 + (2.5)
42.25 = x^2 + 6.25 subtract 6.25 from both sides
36 = x^2 and x = 6
