若4X-3y-6z=0 x=2y-7z=0(x*y*z≠0) 求代数式 5x*5x+2y*2y-6z*6z/2x*2x-
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
如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y,
已知x、y、z满足方程组:x+y-z=6;y+z-x=2;z+x-y=0 求x、y、z的值
已知4x-3y-6z=0,x+2y-7z=0,且x,y,z≠0,求2x+3y+6z/x+5y+5z的值.
已知x::y:z=3:4:5,(1)求x+y分之z的值;(2)若x+y+z=6,求x,y,z.
已知有理数x、y、z满足条件|x-z-2|+(3x-6y-7)^2+|3y+3z-4|=0,求x、y、z
已知方程组4x-3y-6z=0,x+2y-7z=0(z≠0),求x+y+3z/4x-y-5z的值
已知2x+5y+4z=6 3x+y-7z=-4求x+y-z
5x+3y+2z=2011 4x+6y+7z=2012 求x+y+z
若x-y=6,xy=-8,求代数式(x+y+z)²+(x-y-z)(x-y+z)-2·z(x+y)的值
已知{4x-3y-6z=0,x+2y-7z=0 且z≠0.求代数式(2x^2+3y^2+6z^2)/(x^2+5y^2+
已知x+4y+3z=3x-2y-5z=0,求x+2y-z/2x-3y+7z的值