Step by step
The question
Question: the bearing of Y from X is 275°: find the bearing of X from Y.
1 Draw the north line
A bearing starts at the north line.
It is measured clockwise, the way a clock turns, and written with 3 figures.
At Y we draw a north line too.
The two north lines are parallel.
2 Turn round
From Y back to X is the opposite direction: half a turn more, 180°.
275 is more than 180, so we take 180 away: 095°.
Adding would go past 360°.
Why 180?
The north lines are parallel.
The angles between the path and the two north lines add up to 180°, as in the parallel lines lesson.
Careful!
A bearing is under 360°.
Over 180°, we take 180 away.
3 Check
Let's check: the two bearings differ by exactly 180°, half a turn.
So it is right!
Let's look back.
First: draw the north line.
Then: turn round.
Last: check.