Q17 of 25 Page 9

The pillars of equal height stand on either side of a roadway which is 150 m wide. From a point on the roadway between the pillars, the elevation of the top of the pillar are 60° and 30° . Find the height of the pillars and the position of the point.

Formula Used:



Explanation:



From the figure we have,


In ∆ABC,




……. (1)


In ∆DEC,



(from (1))


⇒150 - x = 3x …… (2)


⇒ 4x = 150


⇒ x = 37.5 m


h = 37.5×1.732 = 64.95 m


Height of the tower = 64.95 m


EC = 150 – x


= 150 – 37.5


= 112.5 m


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