Two men standing on same side of a pillar 75 metre high, observe the angles of elevation of the top of the pillar to be 30° and 60° respectively the distance between two men is
Given : CD is the pillar = 75 m
To find : AB = $$x$$ = ?
Solution : In $$\triangle$$ BCD,
=> $$tan(60^\circ)=\frac{CD}{DB}$$
=> $$\sqrt{3}=\frac{75}{DB}$$
=> $$DB=\frac{75}{\sqrt{3}}$$
=> $$DB=25\sqrt{3}$$ -----------(i)
Again, in $$\triangle$$ ACD,
=> $$tan(30^\circ)=\frac{CD}{AD}$$
=> $$\frac{1}{\sqrt{3}}=\frac{75}{x+25\sqrt{3}}$$ [Using (i)]
=> $$x+25\sqrt{3}=75\sqrt{3}$$
=> $$x=75\sqrt{3}-25\sqrt{3}=50\sqrt{3}$$ m
=> Ans - (A)
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