If the declination diagram on a map shows a magnetic declination of 9 degrees west, what would your corrected compass heading be if you follow a 355-degree magnetic heading?

To determine the corrected compass heading when navigating with a magnetic compass, it is essential to consider the magnetic declination indicated on the map. In this case, a magnetic declination of 9 degrees west means that magnetic north is located 9 degrees to the west of true north.

When following a magnetic heading, you need to adjust this heading to find the true heading. To correct the magnetic heading when the declination is westward, you would subtract the declination from your magnetic heading.

Here, the magnetic heading is 355 degrees. By subtracting the 9 degrees west declination from the magnetic heading (355 - 9), the calculation gives you 346 degrees as the corrected heading in true north. This adjustment is essential to ensure accurate navigation.

The other options do not reflect the proper adjustment for the given declination and therefore would not yield the correct true heading in this situation.