9x-5y+z=-6 9x+y-2z=3 -9x+3y-5z=0 求x y z
x/10 = y/8 =z/9 求x+2y+3z/y-5z
若x+2y-9z=0,x-2y+5z=0,(x.y.z≠=0)求2x平方+3y平方+7z平方/x平方-4y平方+4z平方
解方程组2x+y-3z=1,x-2y+z=6,3x-y+2z=9求x,y,z的值
如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y,
x/2=y/3=z/5 x+3y-z/x-3y+z
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
若有理数x,y,z满足(x-1)的2016次方+|2x-y|+lx-3z|=0,求3x-5y-9z的值
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
5x+3y+2z=2011 4x+6y+7z=2012 求x+y+z
已知x/4=y/5=z/6 求x+y+z/3x-2y+z的值
已知x/4=y/5=z/6,求x+y+z/3x-2y+z的值.
已知2x+5y+4z=6 3x+y-7z=-4求x+y-z