Question 1135713:  A woman entering an outside glass elevator on the ground floor of a hotel glances up to the top of the building across the street and notices that the angle of elevation is 52°. She rides the elevator up three floors (60 feet) and finds that the angle of elevation to the top of the building across the street is 34°. How tall is the building across the street? (Round to the nearest foot.) 
  
=              ft 
 Answer by Boreal(15235)      (Show Source): 
You can  put this solution on YOUR website! draw this and there is a triangle with angle A, the complement of the 52 degree elevation, so 38 degrees; B, which is 90 degrees plus 34 degree elevation so 124 degrees; and C, at the top of the other building, which is 18 degrees. sin 18/60 as sin 124/b 
Therefore 60 sin 124=b sin 18 
and b=60 sin 124/sin 18 or 160.97 ft. 
The height of the building is sin 52=height/160.97 
so height is 126.85 or 127 feet. 
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