A 5 m ladder leans against a wall with its foot 3 m from the wall. How high up the wall does it reach?
Answer and explanation
Correct answer: C. 4 m
- Step 1: The ladder is the hypotenuse: h^2 + 3^2 = 5^2. Step 2. h^2 = 25 - 9 = 16, so h = 4. Answer: 4 m. Why not the others: Subtracting or adding lengths directly ignores the Pythagorean relation; adding the squares is wrong.
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