1, 3 Unknown: use it once at (0,0), record the angle, walk about 800 meters, then use it again, record the angle, walk about 100 meters, and then find it yourself until you finally find it.

2 1 known:

Mark the first coordinate S 1, take (0,0) as the center of the circle, make a circle with S 1 as a point on the circle, and then divide the circle into three parts with S 1 as the point (the included angle is 120 degrees), and get the approximate coordinates S2a and S3a of the remaining two parts.

3,2 Known:

Mark the second exact coordinate S2, take (0,0) as the center and S2 as a point on the circle to form a concentric circle, and find the midpoint between its intersection point and the original S3a, that is, the third approximate coordinate S3b.