Q27 of 47 Page 1

From a point P on the ground, the angles of elevation of the top of a 10 m tall building and a helicopter, hovering at some height vertically over the top the building are 30°and 60° respectively. Find the height of the helicopter above the ground.


Let A be the point where the helicopter is present and BC be the height of the building


Given:


BC = 10m


BPC = 30°


APC = 60°





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Answer: The Height above which the helicopter lies above the ground is 30 m


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