A 1.00 kg particle has the xy coordinates (-1.20 m, 0.500 m) and a 3.00 kg particle has the xy coordinates (0.600 m, -0.750 m). Both lie on a horizontal plane. At what (a) x and (b) y coordinates must you place a 1.00 kg particle such that the center of mass of the three-particle system has the coordinates (-0.500 m, -0.700 m)?