{2x+y=10 {x-y+z=4 {3x-y-z=0
若{x+3y+10z=0 则 (x+y-z)/(x-y+z)
已知,方程组:4x-3y-7z=0 x+2y=10z 则(x-y+z)÷(x+y+z)=——
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
若4x-3y-6z=0,x+2y-7z=0,求代数式5x*5x+2y*2y-z*z/2x*2x-3y*3y-10z*10
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)=
已知3x-2y-5z=0,2x-5y+4z=0,且x,y,z均不为0,求3x*x+2y*y+5z*z/5x*x+y*y-
如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y,
x+2y+3z=10,x-y+4z=10,x+3y+2z=2
x-3y+z=0,3x-2y-4z=0,则x:y:z=多少?
x-y+4z=10,x+3y+2z=2,x+2y+3z=11.