A ladder 5 m long leans against a vertical 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: 5^2 = 3^2 + h^2. Step 2. h^2 = 25 - 9 = 16, so h = 4 m. Answer: 4 m. Why not the others: 2 m: Subtracting the lengths ignores the right angle. 8 m: Adding the lengths ignores the right angle. 5 m: That is one more than the height the theorem gives.
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