4x-3y-3z=0x-3y-z=0（1）求x：z（2）求x：y：z（3）求xy+2yz/x方+y方-z方

2x+z=10 x+y-z=4 3x-y-z=0 若|x+3|+|y-2|+|2×z+1|=0求(x×z-y×z)(y-x+z)的值 已知4x-3y-3z=0 x-3y-z=0 (1)求x:y:z 3X+Y+Z=0,2X-Y+3Z=1,X+2Y-Z=4 已知x+y+z=0求证x*x*x+y*y*y+z*z*z=3xyz 证明 ：x/(y+z)+y/(z+x)+z/(x+y)>=3/2其中 x,y,z>0 1.{x:y:z=3:4:5 2x+3y-5z=-142.{x-y-z=-1 3x+5y+7z=11 4x-y+2z=-13.{x+y=1 x+z=0 2x+y+2z=44.{x-y+z=-3 2x-y-z=-2 -3x+y+z=-15.{x-y+z=-3 3x+y-4z=6 2x+y-z=36.{x-2y+5z=16 2x+y-5z=7 2x-y+z=38 x+2y-z=-5 x+y+2z=-1 3x+4y-2z=-12x+2y-z=3 2x+y+3z=0 4x+z=-4 4x-3y-3z=0 x-3y+z=0 并且X Y Z不等于0 求x:z 和y:z的值 方程组｛4x-3y-3z=0,x-3y+z=0,(x.y.z不等于0),求x/z和y/z的值? 已知4x-3y-3z=x-3y+z=0(x、y、z不等于0)(1)求x：y：z （2）求2x+3y-4z/z的值 {x+y+z=4 {2y+z=0 {3x+2y-4z=-1解方程 x+2y-z=0 2x-3z=1 3x-y+2z=4x+2y-z=02x-3z=13x-y+2z=4 {2x+y=10 {x-y+z=4 {3x-y-z=0 已知x-y/x+y=y+z/2(y-z)=z+x/3(z-x),求证8x+9y+5z=0THX.. 已知4x-3y-3z=0,x-3y-z=0求(1)x:z的值.（2）x:y:z的值. 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 已知 x-3y+z=0 3x-3y-4z=0,则x:y:z=已知x-3y+z=0 3x-3y-4z=0则x:y:z=