{x+y-3z=3① y+z-3x=-4② x+z-3y=-1③

x+y/2=z+x/3=y+z/4 x+y+z=27 x+2y=3x+2z=4y+z 求x:y:z x,y,z不是0.3z=4y,z=3x求（x+y）：（x+z）. 已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求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) (x+y):(y+z):(z+x)=3:4:5 3x+y-z=-4已知(x+y):(y+z):(z+x)=3:4:5 ；3x+y-z=-4求x y z 2x+z=10 x+y-z=4 3x-y-z=0 x=y/z=z/3,x+y+z ＝12,求2x+3y+4z是多少, 解方程组x+y/2=z+x/3=y+z/4①x+y+z=27② 已知4x-3y-3z=0,① x-3y+z=0,②并且z不等于0,求x：z与y：z 解三元一次方程组 ①2x-y+z=1 3x+y -2z=2 X+2y-z=3 ②x-4y+z=-3 2x+Y-Z=18 X-Y-Z=7 ③4x+4y+2z=7 6X-4y-z=6 2x-y+z=1 (4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=? x+y-z=3 y+z-x=5 z+x-y=7 求x,y,z 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 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? 3x-y+z=4,2z+3y-z=12,x+y+z=6的解