Question

A ship sailed on a bearing 140 degrees. It was then 90 km south of its orignal position.

a) draw a diagram to show the ship's journey

b) how far east of its original position is it?


what ratio would i need? (sine,cosine or tangent)

i know that all trig questions have a right-angled triangle but where would i put the angle(140) and the line(9)

thanks in advance :)

Answer 1

A bearing of 140 degrees is measured clockwise from north, and is generally called azimuth in North America.

This translates to S40E in general terms, or (90-140)=-50 degrees in trigonometry (4th quadrant, cosine >0, sine <0)

If the ship was 90 km south of its original position, then
D sin(-50°)=-90 km
from which you can calculate D, the distance travelled in the direction of 140° in km.