若2x-3y+4z=7,3x+2y-z=2,x-8y+9z=?

若4x-3y-6z=0,x+2y-7z=0,则x+y+z/3x-y+z=? 若x+y+z=3y=2z,则x/x+y+z=? x+2y=3x+2z=4y+z 求x:y:z x+y/2=z+x/3=y+z/4 x+y+z=27 试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y) 已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z 若X:Y:Z=5:6:7那么(Y-X):(Y+Z)和(X+2Y+3Z):(3X+2Y+Z) 解方程：{2x+3y+z=7,x+y+z=4,3x+y-z=-4{2x+3y+z=7,x+y+z=4,3x+y-z=-4要过程 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, 若|x+3|+|y-2|+|2×z+1|=0求(x×z-y×z)(y-x+z)的值 已知x/2=y/4=z/7,求①x：y：z.②若2x+y+3z=58,分别求x,y,z的值.③求x+y/x+z的值. x：y：z=3:4:7 2x-3y+z=18 求：3x-2y+z 若x/2=y/3=z/4,则3x-2y+5z/x+y+z= x+2y+4z=17 2x+y+z=7 3x+y+2z=11 2x+5y+4z=6,3x+y-7z=-4,x+y-z=? 若x/3=y/4=z/5,求x+y+z/3x-2y+z的值. 若x:y:z=2:3:4,求x+y+z/x-2y+3z的值