Q15 of 25 Page 9

The angle of elevation of the top of the building from the foot of the tower is 30° and the angle of the top of the tower from the foot of the building is 60°. If the tower is 50 m high, find the height of the building.

To find:


The height of the building.


Formula Used:



Explanation:



Let AB be the building of height 50 m. and tower of height h (m.)


In ∆ABC


tan 60° =


√3 =


….. (1)


Now in ∆DCB


tan 30° =



…. (2)


On substituting value of in eqn. (1)



√3h =


h =


h =


Therefore, height of tower is m.


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