Complex Addition/Examples/Travel 2

Example of Complex Addition
An airplane travels:
 * $150$ kilometres southeast

then:
 * $100$ kilometres due west

then:
 * $225$ kilometres $30 \degrees$ north of east

then:
 * $323$ kilometres northeast.

Assuming the curvature of the Earth to be negligible at this scale, at the end of this travel, the plane is $490$ kilometres in a direction $28.7 \degrees$ north of east from its starting point.