Question

The angle of depression of the top and bottom of 8m tall building from the top of a transmission tower fixed at the top of 20m high building one 45° and 60° respectively. Find the height of the tower.​

Answer 1

Let AB and CD be the multi-storeyed building and the building respectively.

Let the height of the multi-storeyed building= h m and

the distance between the two buildings = x m.

AE = CD = 8 m [Given]

BE = AB – AE = (h – 8) m

and

AC = DE = x m [Given]

Also,

∠FBD = ∠BDE = 30° (Corresponding angles)

∠FBC = ∠BCA = 45° (Corresponding angles)

Now,

In Δ ACB,

(refer to the attachment 2 and 3)