Question

A,B and C are three points on a straight line (in that order) on horizontal ground. A and B are on the side of C. At C stands a vertical tower 173.2m high. The distance from A to B is 100m and the angle of elevation of the top of the tower from A is 30°. Find the angle of elevation of the top of the tower from B.

Answer 1

 Tan 30  =      173.2  
                  (100+BC)
 100 +BC =   173.2  
                    Tan 30
100 +BC =300
        BC  = 300−100
         BC =200m
Tan θ =173.2
             200
      θ =40.89°