1. The problem statement, all variables and given/known data An observer, on a ship A sailing to the north with speed of 7km/h, saw a ship B. Ship B seems to be moving to south-east with a speed of 12√2 km/h. Find the direction which B is heading to. 2. Relevant equations 3. The attempt at a solution Let i and j be the unit vectors in the direction of eat north respectively and VA = velocity of ship A and VB = velocity of ship B. Now, VA = 7j BVA = 12i - 12j VB = BVA + VA =12i - 5j so θ = tan-15/12 = 22.6° The direction of ship B is E22.6°S. But the answer given is N67°23'E, which step is incorrect? Can anyone enlighten me?