The tops of two towers of heights x and y, standing on a level ground subtend angles of 30° and 60° respectively at the centre of the line joining their feet. Then, x : y is

Untitled37.jpg


Let BC = x and AD = y be the two towers. They subtend angles 30° and 60° at the centre of the line joining their feet say P. Join C, P, D. Also join B, P and A, P. So, BPC = 30° and APD = 60°. Also, we get two right-angled triangles BPC and APD with right angles at C and D respectively. We have to find x:y.


From ∆BPC,



or,



or,



From ∆APD,



or,



or,


y = PD√3


So, taking the ratio we get,



Hence, the correct choice is C.

17