Solve: 2x+y−z=52x + y - z = 52x+y−z=5, y+2z=4y + 2z = 4y+2z=4, z=1z = 1z=1.
(2,2,1)(2, 2, 1)(2,2,1)
(1,2,1)(1, 2, 1)(1,2,1)
(2,1,1)(2, 1, 1)(2,1,1)
(3,2,1)(3, 2, 1)(3,2,1)