The angle of elevation of the top of a tower from the top of a building whose height is
680 m is 45° and the angle of elevation of the top of same tower from the foot of the
same building is 60°. What is the height (in m) of the tower?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e.340(3 + √3)
Let AB be a building = 680 m
The CD is a tower
As shown in the figure
In triangle ACE
tan 45º = CE/BD
CE = BD = CD - 680
In triangle CBD
tan 60º = CD/BD
CD = BD√ 3
AB = CD - CE
CD = AB + CE = 680 (√ 3 - 1)/√ 3
CD = 340(3 + √3) m