已知x除以2=y除以3=z除以-7≠0

已知x除以2=y除以3=z除以-7≠0 已知x除以2=y除以3=z除以4,且x≠0,求x+y+z除以x-2y+3z的值, 已知x+y除以5=y+z除以6=z+x除以7,且xyz≠0,求x比y比z 若x+y除以3=y+z除以5=z+x除以4,且xyz≠0,则x:y:z=? 已知x+2y-3z=0,2x+3y+5z=0,求(x+y+z)除以（x-y+z) 已知2x+3y-4z=0,3x+4y+5z=0,求x+y+z/（除以）x-y+z的值. 已知2x+3y-4z=0,3x+4y-5z=0.求x+y+z除以x-y+z, 已知x+2y-3x=0,2x+3y+5z=o.求x+y+z除以x-y+z 若x除以10=y除以8=z除以9,则x+y+z除以y+z （x+y）除以2=（y+z）除以3=（z+y）除以4,x+y+z=27这个方程怎么解啊. x除以2=y除以3=z除以5 2x+y+3z=88 求x = y = z= 已知X除以3等于Y除以4等于Z除以5,求X加Y除以X减2Y加3Z