Answer:
41
Step-by-step explanation:
Applying Pythagoras theorem since it is a right angled triangle.
(Hypotenuse)^2=(base)^2+(perp)^2
Hyp^2=(9)^2+(40)^2
Hyp^2=81+1600
Hyp^2=1681
Taking sq root on both sides
Hypotenuse=41