to find the position vector coordinates, you need to find X and y
complete the hidden triangle so you can find the coordinates ( Refer to my pic)
find AO by using trigonometry : cos13= adj / hypotenuse = AO/ 5
AO is around 4.8718 which is X coordinate for point B
Find AB by trigonometry or you could use Pythagorean theorem
sin13= opp/ hypotenuse = AB/5
AB is around 1.124 which is y coordinate for point B
Position vector OB has coordinates around (-4.9, -1.1)