解方程组.大括号:X-2Y+4Z=12 3X+2Y+Z=1 4X-Z=7
解方程组{3x+y-z=4,2x-y+3z=12,x+y+z=6}
解方程组:2x+3y+4z=20,x+y+z=7
解方程组:{3x+2y+2z=-1 4x-3y-5z=12 2x+6y+7z=-1
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1、4x+9y=12,3y-2z=1,2x+6z=32、3x-y+2z=3,2x+y-3z=11,x+y+z=1
解三元一次方程组:{x+y+z=4 2x+y+3z=9 x+3y+2z=14 {3x+y-z=7 x+2y+2z=12
解下列方程组(1)3x-y+z=3 2x+y-3z=11 x+y+z=12(2)5x-4y+4z=13 2x+7y-3z
解三元一次方程组 {2x+y+3z=1 y-2z=4 3x+y=9 {2x+y+z=9 y-2z=-12 3x+y=7
大括号2x+3Y-z=11 2x+y-5z=8 -2x+7y+z=19的3元一次方程组!
已知,方程组:4x-3y-7z=0 x+2y=10z 则(x-y+z)÷(x+y+z)=——