Trigonometry · SS 2
Bearings and back bearings
Find the bearing for the return journey.
- Back bearing = bearing + 180° (if the bearing is less than 180°)
- Back bearing = bearing − 180° (if the bearing is 180° or more)
What the letters mean
- bearing
- an angle measured clockwise from North, written with three figures
Worked example
The bearing of B from A is 070°. Find the bearing of A from B.
Step 1: 070° is less than 180°, so add 180°
070° + 180° = 250°
Final answer: 250°
See it
Play with this picture from the Bearings and Distances lesson.
Bearing of B from A
065°
Back bearing (A from B)
245°
065° + 180° = 245°
B is 2.54 km north and 5.44 km east of A.
Distance A to B6 km