Question
From the top of a multi-storey building, the angle of
depression to the top of a smaller building (which is 20 meters tall) is 45°. The distance between the two buildings is 15 meters. Find the height of the multi-storey building.Solution
ATQ, Let AB be the multi- storey building and CD the small building. In triangle APC 
Therefore, the total height AB = AP+BP = 15+20 = 35 meters.
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