七上数学教与学方程组题：x/2-y/3-z/4=3x/2+y/3-z=4x/3-y/2+z/2=3

已知方程组2x-3y-4z=0和x+y+z=0,并且z≠0,求x：y与y：z 解方程组{3x+y-z=4,2x-y+3z=12,x+y+z=6} 已知方程组4x-5y+2z=0 x+2y=3z 则x:y:z 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 求解三元一次方程组：｛x+y/2=y+z/3=z+x/4 x+y+z=27 方程组:x-2y+4z=0,2x+3y-3z=0...xyz不等于0,求(2x+y-z)\(2x-y+z) 已知,方程组:4x-3y-7z=0 x+2y=10z 则(x-y+z)÷(x+y+z)=—— 已知方程组4x-y+3z=0 2x+y+6z=0且xyz不等于0,则x/y+y/z+z/x是多少 4x-3y-6z=0,x+2y-7z=0是一个方程组,那么x-y+z/x+y+z的值等于 解三元一次方程组：x+y+z=6,y-z=4,x-y-2z=3,