解方程组解方程组｛y=2x-7｛x+y+z=1｛3x-z=4

解方程组：2x+3y+4z=20,x+y+z=7 2x+y=4,x+3z=1,x+y+z=7解这个三元一次方程组 解方程组2x+y-z=7 x+y+z =1 2x-y-z=5 解方程组：x-2y+z=-1,x+y+z=2,x+2y+3z=-1 解方程组{3x+y-z=4,2x-y+3z=12,x+y+z=6} 解方程组x-4y+z=-3,2x+y-z=18,x-y-z=7. x+y/2=z+x/3+y=z/4,...x+y+z=27.解方程组. 解方程组：x+y+z=4,x+y+2z=5,3x+y-z=6 解方程组x+2y-z=1 ,3x-3y+z=2,2x+3y+z=7和方程组x+y=-14,y+z=-7,x+z=19 解方程组：{x/2=y/3=z/4 2x+y+z=22 解方程组：3x+7y+z=31.5,4x+10y+z=42 x/2=y/3=z/4 x+y+z=18 求方程组解