Question

A bird is flying from A towards B at an angle of 35°, a point 30 km away from A. At B it changes its course of flight and heads towards C on a bearing of 48° and distance 32 km away. How far is C to the East of B?
(sin 55° = 0.8192, cos 55° = 0.5736, sin 42° = 0.6691, cos 42° = 0.7431)

Answer 1

The distance of C to the East of B is BD

In the right ∆BDC, 

cos 42° = `"BD"/"BC"`

0.7431 = `"BD"/32`

∴ BD = 0.7431 × 32

= 23.78 km

Distance of C to the East of B is 23.78 km.