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प्रश्न
The horizontal distance between two towers is 75 m and the angular depression of the top of the first tower as seen from the top of the second, which is 160 m high, is 45°. Find the height of the first tower.
उत्तर
Let AB and CD be the two towers.
The height of the first tower is AB = 160 m
The horizontal distance between the two towers is BD = 75 m
And the angle of depression of the first tower as seen from the top of the second tower is ∠ACE = 45°
In ΔACE,
`(AE)/(EC) = tan 45^circ = 1`
`=>` AE = EC = BD = 75 m
∴ CD = EB
= AB – AE
= (160 – 75)
= 85 m
Hence, height of the other tower is 85 m.
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