x-y=3/2 x+z=7/10 y-z=-6/5三元一次方程组

X/10=Y/8=Z/9,则X+Y+Z/2Y-3Z 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+2y+3z=11,x-y+7z=10,x+3y+2z=2 X=3z X+y+z=12 X+2y-2z=10 2x+z=10 x+y-z=4 3x-y-z=0 已知4x-3y-6z=0,x+2y-7z=0,求5x+2y-z/2x-3y-10z 已知,方程组:4x-3y-7z=0 x+2y=10z 则(x-y+z)÷(x+y+z)=—— (4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=? {x+y+z=1;x+3y+7z=-1;z+5y+8z=-2 x+2y+3z=23 y-z=5 x+2z=10 x+y-z=3 y+z-x=5 z+x-y=7 求x,y,z 证明 ：x/(y+z)+y/(z+x)+z/(x+y)>=3/2其中 x,y,z>0 (4x-2y-z)-{5x-[8y-2z-(x+y)]-2(3y-10z)}=?好难啊 x+y+z=14 7z=x+y+2 x+z=y x/2=y/3=z/5 x+3y-z/x-3y+z x+y/2=z+x/3=y+z/4 x+y+z=27 若x+y+z=3y=2z,则x/x+y+z=?