Let the starting point be the origin. When car moves 2m towards north the car is at (0,2), know the car take a left turn and moves 4 Km, now the position of the car is (4,2). Now car takes right turn and moves 1 Km. Now the car is at (4,3). The initial position of car is (0,0), the final point is (4,3). The shortest distance between this point is 5Km