Question

Austin buys a new moped he travel 3 km south and then 4 km east and then 3km north how far does he need to go to get back to where he started

Answer 1

The first thing to do is to define the origin of the coordinate system as the point at which the moped journey begins.
 Then, you must write the position vector:
 r = -3j + 4i + 3j
 Rewriting
 r = 4i
 To go back to where you started, you must go
 d = -4i
 That is to say, must travel a distance of 4Km to the west.
 Answer
 West, 4km.