What is being done to A to get B? Move A around and watch what happens to B.
If you put A on (2,0) what happens to B? If you put A anywhere on the x axis where will B be? If you put A on (0,2) what happens to B? If you put A anywhere on the y axis where will B be? If you put A on (3,2) what happens to B? If you put A on (-3,-2) what happens to B?