已知3x=4y=5z,且x不等于0,求2x-3y+6z/3x-2y+4z=?初二线段的比.

已知x/2=y/3=z/4,且x+y+z不等于0,求2x+3y-4z/x+y+z的值 已知x/2=y/3=z/4,且x+y+z不等于0,求2x+3y-4z/x+y+z的值 已知4x-5y+2z=0,x+4y-3z=0 且xyz不等于0,求x:y:z的值. 已知xyz不等于0,且x/3=y/4=z/5,求【2x-3(2y-z)】/x+y+z 已知4x-5y+2z=0,且x+4y-3z=0,(xyz不等于0）试求x/y 已知4x-5y+2z=0,且x+4y-3z=0,(xyz不等于0）试求x/y 已知方程组{2x-3y+z=0 且x*y*z不等于0 求 x：y：z {3x-2y-6z=0 已知2x-y-3z=0 x-2y+z=0,且x、y、z都不等于0,求x：y：z 已知x/2=Y/3=Z/4且xyz不等于0,求2X+3Y-Z/X-3Y+Z的值. 已知2X+5Y+4Z=0,3X+Y-7Z=0,且XYZ不等于0,求（X+Y+Z）/(2X-3Y+4Z)的值 已知2X+5Y+4Z=0,3X+Y-7Z=0,且XYZ不等于0,求（X+Y+Z）/(2X-3Y+4Z)的值 已知xyz不等于0,且2x-y+z=0,x-2y+3z=0,求代数式(x²+3y²+5z²)/(2x²+4y²+7z²)的值 已知方程组4x-y+3z=0 2x+y+6z=0且xyz不等于0,则x/y+y/z+z/x是多少 已知方程组{X+Y-7Z=0(1)3X-2Y-Z=0(2)且Z不等于0求X:Y:Z 已知x,y,z满足方程组x-2y+z=0 7x+4y-5z=0,且z不等于0,2x²-3y²+z²/y²-2z²的值为? 已知xy/5=y+z/6=z+x/7,且xyz不等于0,求x:y:z 若xyz不等于0,且{4x-5y+2z=0,x+4y-3z=0,求x:y:z 若xyz不等于0,且4x-5y+2z=0,x+4y-3z=0,求x：y：z的值.