If someone wants an angle that is relative to north with east of north positive and west of north negative, what does that mean? Is that the positive x axis? My guess is the positive y axis, since 90 degrees would have those conditions, but not sure.. Here is the problem that's brought up this confusion: A train at a constant 75.0 km/h moves east for 39 min, then in a direction 42.0° east of due north for 13.0 min, and then west for 69.0 min. What are the (a) magnitude and (b) angle (relative to north, with east of north positive and west of north negative) of its average velocity during this trip? I have a, which is 14.6 km/h. But for b I get an angle of -24.6 (x component = -13.3, y component = 6.1). I have no idea how to adjust the angle, -24.6, to satisfy b. My only idea is to draw it and adjust from there, but I first need to know where exactly they want the equivalent angle, which I don't understand from their wording.