A ladder 41 m long leans against a vertical wall with its foot 9 m from the wall. How high up the wall does it reach?
Answer and explanation
Correct answer: C. 40 m
- Step 1: The ladder is the hypotenuse: 41^2 = 9^2 + h^2. Step 2. h^2 = 1681 - 81 = 1600, so h = 40 m. Answer: 40 m. Why not the others: 32 m: Subtracting the lengths ignores the right angle. 50 m: Adding the lengths ignores the right angle. 41 m: That is one more than the height the theorem gives.
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