Q51 of 68 Page 9

A building subtends a right angle at the top of a pole on the other side of the road. The line joining the top of the pole and the top of the building makes an angle of 60° with the vertical. If the width of the road is 45 m, find the height of the building.


Given: Width of the road = 45m


In right Δ BCD, we have




⇒ CD = 15√3 m


∴ CD = BE = 15√3 m


Now, In ΔAED, we have




⇒ AE = 45√3 m


Now, the height of the building = AE + BE = 45√3 + 15√3


= √3(45 + 15)


= 60√3 m


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