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The angles of elevation of the top of a tower from two points A and B at distances of 4 m and 9 m from the base on the same side are complementary. The height of the tower is
A5 m
B6 m
C7 m
D9 m
Answer & Solution
Correct answer: B. 6 m
1. Let angles be theta and 90 - theta; tan(theta) = h/4 and cot(theta) = h/9.
2. Multiply: 1 = h squared / 36.
3. h squared = 36, so h = 6 m.
_Source: NCERT Class 10 Mathematics, Ch 9 "Some Applications of Trigonometry", §9.2_
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