Solve: y=2xy = 2xy=2x and x+y=3x + y = 3x+y=3.
(1,2)(1, 2)(1,2)
(2,1)(2, 1)(2,1)
(1.5,1.5)(1.5, 1.5)(1.5,1.5)
(0,3)(0, 3)(0,3)