A ladder is leaning against a wall. The base of the ladder is 5 feet from the wall, and the ladder reaches 12 feet up the wall. What is the length of the ladder?
✓ Correct Answer: Option B
This forms a right triangle. Use the Pythagorean theorem (a² + b² = c²): 5² + 12² = c². 25 + 144 = 169. c = √169 = 13 feet.