Question 830864
We know that for a right triangle, a^2 + b^2 = c^2, where a and b are the legs and c is the hypotenuse.
You're given the legs.  Plug those values in.
15^2 + 8^2 = c^2
Do the math.
225 + 64 = c^2
Add
289 = c^2
Find the square root
17 = c