3X+2y+z=20 x+y+z=10 Y=3X
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
x/2=y/3=z/5 x+3y-z/x-3y+z
若{x+3y+10z=0 则 (x+y-z)/(x-y+z)
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
已知x,y,z 大于0,x+y+z=2,求证 xz/y(y+z)+zy/x(x+y)+yx/z(z+x)大于等于2/3
(x+y-z)(x-y+z)=
如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y,
三元一次方程组数学题x+2y+2z=33x+y-2z=72x+3y-2z=10x-y=2z-x=3y+z=-1x-y-z
x+2y+3z=10,x-y+4z=10,x+3y+2z=2
x-y+4z=10,x+3y+2z=2,x+2y+3z=11.
x+y+z=4 2x+3y-z=6 3x+2y+2z=10
3x+2y+z=14 ,x+y+z=10,z+2x+3y=1 5