Question

Alice is standing on the roof of a 150 ft building. She looks down at an angle of depression of 15 degree and sees her friend bianca. How far away from the building is bianca

Answer 1

559.70 ft

Explanation:

Let D be the distance between building and Bianca.

Height of building H = 150 ft

Let there be a triangle ABC where, AC = height of building H= 150ft, AB = distance between Alice and Bianca and BC = D and therefore, ∠ABC = 15°.

Now in Triangle ABC , tanB = AC/BC

therefore, tan15° = 150/D

D = 150/tan15° = 559.70 ft

Therefore, the distance between building and Bianca D = 559.70 ft