3x-4y+2z=2 (1)x+4y+z=-3 (2)2x-2y+3z=-4 (3)(1)+(2)4x+3z=-1 (4)(2)+(3)*25x+7z=-11 (5)(4)*7-(5)*328x-15x=-7+3313x=26所以x=2z=(-11-5x)-7=-3y=(3x+2z-2)/4=-1/2
