{2x+3y=-1,3x+4y-3z=-7,-2x+3y+3z=1急需啊!

x+y/2=z+x/3=y+z/4 x+y+z=27 x+2y=3x+2z=4y+z 求x:y: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) 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 分式加减的几道题目求速度1 .(x+y)²/（x-z)(y-z) - (y+z)²/（x-z)(y-z) = 2.2x+3y/x-y+2y/y-x-3y/x-y= x:y=3:4 y:z=2:1 x+y+z=20 急! (4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=? x+y+z=6 x+2y+3z=14 y+1=z 4x+y+z=-3 2x+3y-4z=-10 x+2y-z=-1 x-y-z=1 2x+y-3z=4 3x-2y-z=-1 x+y-z=6 x-3y+2z=1 3x+2y-z=4 阿 x+y-z=6,x-3y+2z=1,3x+2y-z=4 x+y+z=-5,3x+y+z=1,4x+3y+2z=-2快 3x+2y+z=4 x+y+z=10 2x+3y-z=1 x+y-z=6 x-3y+2z=1 3x+2y-z=4 3X+Y+Z=0,2X-Y+3Z=1,X+2Y-Z=4