3x+y+z=6 x+3y+z=5 x+y+3z=9

x+y-z=3 y+z-x=5 z+x-y=7 求x,y,z x/2=y/3=z/5 x+3y-z/x-3y+z 6x+5y+3z=100 x+y+z=30 求 x y 已知3X=4X,5Y=6Z求X+Y：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x-y/x+y=y+z/2(y-z)=z+x/3(z-x),求证8x+9y+5z=0THX.. 若X:Y:Z=5:6:7那么(Y-X):(Y+Z)和(X+2Y+3Z):(3X+2Y+Z) 解方程组3x+y+z=6,x+3y+z=5,x+y+3z=9｛3x+y+z=6｛x+3y+z=5｛x+y+3z=9 x+y+z=6 x+2y+3z=14 y+1=z (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 y+z-3x=3z+x-3y=5x+y-3z=6 x/3=y/6=z/8 3x+5y-6z=-18 求x,y,z 3x+y+z=6 x+3y+z=5 x+y+3z=9 {2x+3y-4z=-5 x+y+z=6 x-y+3z=10 x-y+z=-1 5x+2y-z=6 4x-3y+2z=-5 2x+5y+4z=6,3x+y-7z=-4,x+y-z=? x+y+z=1 4x+5y-z=6 x+2y-z=3