Which step uses two back azimuths to determine your current grid coordinate?

Which step uses two back azimuths to determine your current grid coordinate?

• A. Intersection
• B. Resection
• C. Distance measurement
• D. Map rectification

Answer: (A)

Two back azimuths let you triangulate your position on the map. You observe two known features and measure the bearing from your location to each feature (the back azimuths from those features toward you). On your map, plot a line from each feature in the direction of its back azimuth. The point where those two lines cross is your current grid coordinate. This crossing-line method is why that step is the one that uses two back azimuths to determine your position. Distance measurement would use a known distance to a feature and a circle of possible positions; map rectification is about aligning the map to the terrain and doesn’t pinpoint your location with two bearings.

Two back azimuths let you triangulate your position on the map. You observe two known features and measure the bearing from your location to each feature (the back azimuths from those features toward you). On your map, plot a line from each feature in the direction of its back azimuth. The point where those two lines cross is your current grid coordinate. This crossing-line method is why that step is the one that uses two back azimuths to determine your position. Distance measurement would use a known distance to a feature and a circle of possible positions; map rectification is about aligning the map to the terrain and doesn’t pinpoint your location with two bearings.