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Question
A man stands 9 m away from a flag-pole. He observes that angle of elevation of the top of the pole is 28° and the angle of depression of the bottom of the pole is 13°. Calculate the height of the pole.
Solution
Let AB be the man and PQ be the flag pole
Given, AR = 9 m
Also, ∠PAR = 28° and ∠QAR = 13°
∴ `(PR)/(AR) = tan 28^circ`
`=>` PR = 9 × 0.532 = 4.788 m
Also, `(RQ)/(AR) = tan 13^circ`
`=>` RQ = 9 × 0.231 = 2.079 m
Hence, height of the pole = PR + RQ = 6.867 m
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