Question

An aeronplane leaves an airport A and flies on a bearing 035 for 1.5 hours at 600 kilometers per hour to an airport B . It then flies on a bearing 130 for 1.5 hours at 400 kilometers per hour to an airport C calculate the distance from C to A, correct to the nearest kilometers.
Bearing of C from A, correct to nearest degree.

Answer 1

Regular

Answer 2

AB = 1.5 * 600 = 900 km
BC = 1.5 * 400 = 600 km
To find AC, use the law of cosines.
AC^2 - 900^2 + 600^2 - 2*900*600 cos85°
adding the vectors AB+BC, we have
900cis55° + 600cis(-40°) = 975.8 + 351.6i
That means that C is on a bearing of 90-19.8 = 70.2°