Q48 of 68 Page 9

A vertical tower of height 12m subtends a right angle at the top of a flagstaff If the distance between them is 12 m, find the height of the tower.


Let AB be the Flagstaff and CD be the vertical tower


let the height of the tower, CD = h


∵ AB = EC = 12 m


and the distance between Flagstaff and tower = 12 m


Hence, BC = AE = 12 m


Now, In Δ ABC, we have




⇒ tan x = tan 45°


⇒ x = 45° …(i)


Now, In ΔADE, we have



[from(i)]




⇒ DE = 12 m


Hence, the height of the tower, CD = DE + CE = 12 + 12 = 24m


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