X:Y=3:4,Y:Z=6:5=X:Y:Z=( ):( ):( )
已知3X=4X,5Y=6Z求X+Y:Y+Z
(x+y-z)(x-y+z)=
X:Y=3:4,Y:Z=6:5=X:Y:Z=( ):( ):( )
2x+5y+4z=6,3x+y-7z=-4,x+y-z=?
{2x+3y-4z=-5 x+y+z=6 x-y+3z=10
3x+7y+z=5 ,4x+10y+z=6 ,x+y+z=
解方程组:x+y+z=4,x+y+2z=5,3x+y-z=6
已知2x+5y+4z=6 3x+y-7z=-4求x+y-z
5x+3y+2z=2011 4x+6y+7z=2012 求x+y+z
已知x/4=y/5=z/6 求x+y+z/3x-2y+z的值
已知x/4=y/5=z/6,求x+y+z/3x-2y+z的值.
若x:y:z=3:4:5=6,求x-y+z分之x+y-z的值