Question

If the bearing from `A` to `B` is `042°`, what is the bearing of `B` from `A`?

Answer 1

`042°+180° = 224°`

Explanation:

The bearing of B from A is known as the reverse bearing of the bearing of A from B.

Reverse bearings differ by `180°`

South is the reverse bearing of North
`000° +180 = 180°`

West is the reverse bearing of East
`090° + 180° = 270°`

South-west is the reverse bearing of North-east.

`045° +180° = 225°`

To find a reverse bearing, add or subtract `180°`

The bearing of B from A = `042°+180° = 224°`