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Question
From the top of a cliff 92 m high, the angle of depression of a buoy is 20°. Calculate, to the nearest metre, the distance of the buoy from the foot of the cliff.
Solution
Let AB be the cliff and C be the buoy.
Given, AB = 92 m
Also, ∠ACB = 20°
∴`(AB)/(BC) = tan 20^circ`
`=> BC = 92/0.3640 = 252.7 m ≈ 253 m`
Hence, the buoy is at a distance of 253 m from the foot of the cliff.
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