Question

The angles of elivation and depression of top and bottom of a tower from the top of a building 60m high are 30° and 60° respectively.Find the difference between the heights of the building and tower and also the distance between them.

Answer 1

Answer:

see attached figure, here it is clear that height of building, AB = 60m.

height of tower = EC.

elevation angle,  = 60°

depression angle,  = 30°

we have to find , difference between the height of building and tower e.g., ED.

from ∆DAE,



or, tan30° = ED/AD

or, 1/√3 = ED/AD => AD = √3ED .....(1)

from ∆ABC,



or, tan60° = AB/CB

or, √3 = 60/AD [ from figure , AD = CB ]

or, √3AD = 60

from equation (1),

√3 × √3 ED = 60

or, 3ED = 60 => ED = 20m

Answer 2

plz refer to this attachment