I came across this question in a past paper, and am absolutely stuck. A coastguard station 0 monitors the movements of ships in a channel. At noon, the station's radar records two ships moving with constant speed. Ship A is at the point with position vector (-5i + 10j) km relative to 0 and has velocity (2i + 2j) km/h. Ship B is at the point with position vector (3i + 4j) km and has velocity (-2i + 5j) km/h. (a) Given that the two ships maintain these velocities, show that they collide. Is there anyone who can help? Even if it's just tips on where to start etc? Thanks in advance!