Q30 of 49 Page 1

Two poles of equal heights are standing opposite to each other on either side of the road, which is 100 m wide. From a point between them on the road, the angles of elevation of the top of the poles are 60 � and 30 � respectively. Find the height of the poles.


Let AB and DE be equal poles that are 100m apart and the height of the poles be y m.


Let the point C be the point on road, x m far from AB.


Now Distance of C from DE will be (100-x) m.


In Δ ABC,




………(1)


In Δ CED




y√3=100-x


Putting the value of x from eq(1)





4y=100√3



y=25(1.73)=43.25m


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