Answer:
C. 17
Step-by-step explanation:
Use Pythagorean's theorem: a² + b² = c²
(side length² + side length² = hypotenuse²)
1. Set up the equation
8² + 15² = c²
2. Simplify
64 + 225 = 289
289 = c²
3. Solve by square rooting both sides
√289 = √c²
c = 17
