Q44 of 68 Page 9

Two pillars of equal height are 64 m apart. The angles of elevation of their tops from any point joining their feet are respectively 30° and 60°. Find the height of the pillars.


Let the height of the equal pillars AB = CD = h


Given the width of the road, BD = 64m


Let BE = x. Hence, DE = 64 – x


Now, In right ΔABE, we have





In the right ΔCDE, we have




⇒ 64 – x = √3h






⇒ h = 16√3 m


Hence, the height of the equal pillars AB = CD = 16√3m


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