解方程{x:y=1:2,y:z=1:3,x+y-z=3
x:y:z=1:2:3 x+2y+3z=56解方程
x+2y+3z=28 x:y:z=1:2:3 解方程
解方程一;{x+y-z=6,x-3y+2z=1,3x+2y-z=-7.②{3x+4z=7,2x+3y+z=9,5x-9y
3x-y+z=3 2x+y-3z=11 x+y+z=12 解方程
解方程:{2x+3y+z=7,x+y+z=4,3x+y-z=-4
解方程{3x -y+z=4 2x+3y-z=12 x+y+z=6
解方程组:x-2y+z=-1,x+y+z=2,x+2y+3z=-1
设函数z=z(x,y)由方程x^2+y^3-xyz^1=0确定,求z/x,z/y
解方程组2x+y-3z=1,x-2y+z=6,3x-y+2z=9求x,y,z的值
x+2y=3 x+y+z=36 2x+y+z=15 2y=3z x-y=1 x+2y+z x-z=-1 2x+z-y=1
3元1次方程x-2y=-9 3x-y+z=4{ y-z=3 { 2x+3y-z=122z+x=47 x+y+z=6
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)