解方程组x/7=y/5=z/3,2x+3y-4z=68
解方程组:x+y+z=4,x+y+2z=5,3x+y-z=6
解方程组:2x+3y+4z=20,x+y+z=7
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{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
方程组2x+4y+3z=9,3x-2y+5z=11,5x-6y+7z=13的解是什么
解方程组:{3x+2y+2z=-1 4x-3y-5z=12 2x+6y+7z=-1
方程组x+2y+3z=6 3x-y-z=1 4x+5y-7z=2的解
解方程组3x+y+2z=8,x+y+z=5,2x+3y+4z=7