2x-3y+5z=10,①3x+6y-2z=7,②5x+9y+6z=-2,③①*2+②,7x+8z=27,①*3+③,11x+21z=28,解得x=343/59,z=-101/59,代入①,y=-409/177.∴x=343/59,y=-409/177,z=-101/59.