Q14 of 49 Page 1

The horizontal distance between two poles is 15 m. The angle of depression of the top of the first pole as seen from the top of the second pole is 30 �. If the height of the second pole is 24 m, find the height of the first pole. [use √3 = 1.732]

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Let AB be the 1st pole and CE = 24 m be the 2nd pole


In Δ ADE,


tan 30° = DE/AD


⇒ 1/√3 = DE/15


∴ DE = 15/√3 = 5√3 = 5× 1.732 = 8.66 m


Thus, Height of the first pole = AB = CD = CE-DE = 24-8.66


= 15.34 m


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