解3元方程组 z=x+y 2x-3y+2z=5 x+2y-z=3

解方程组{z=x+y 3x-2y-2z=-5 2x+y-z=3 解方程组 z=x+y 2x-3y+2z=5 x+2y-z=3 解方程组：x+y+z=4,x+y+2z=5,3x+y-z=6 x:y:z=2:3:5解方程组 2x+3y-z=16 解方程组：x+3y=5.y-2z=5.x+z=5 解3元一次方程组：x+y+z=70 x/30+y/20+z/40=2/5 x/40+y/20+z/30=10/23 解方程组：x-2y+z=-1,x+y+z=2,x+2y+3z=-1 解方程组{2x+3y+z=11,x+y+z=0,3x-y+z=-2. 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. 已知方程组4x-5y+2z=0 x+2y=3z 则x:y:z