A ladder 17 m long leans against a vertical wall with its foot 8 m from the wall. How high up the wall does it reach?
Answer and explanation
Correct answer: D. 15 m
- Step 1: The ladder is the hypotenuse: 17^2 = 8^2 + h^2. Step 2. h^2 = 289 - 64 = 225, so h = 15 m. Answer: 15 m. Why not the others: 9 m: Subtracting the lengths ignores the right angle. 25 m: Adding the lengths ignores the right angle. 16 m: That is one more than the height the theorem gives.
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