x+y=7; 5x-2y=-7
4x+y=8; 2x-2y=-6
x-y=2; -3x+5y=0
(1, 4)
x+y=48; x-3y=4
x-2y=0; x-y=12
(5, 3)
(24, 12)
(37, 11)
(0, 3)
(1, 6)
