若x:y:z=2:7:5,且x-2y+3z=6,求:x+y+z的值.
若2分之x+y=3分之y+z=5分之x+z 且x+y+z=18 求x,y,z的值
已知4x-3y-6z=0,x+2y-7z=0,且x,y,z≠0,求2x+3y+6z/x+5y+5z的值.
已知x::y:z=3:4:5,(1)求x+y分之z的值;(2)若x+y+z=6,求x,y,z.
若z≠0,且4x=7y+5z,2x+y=z,求x,y,z的值
已知4x-3y-6z=0,x+2y-7z=0,且x、y、z都不为0,求(3x+2y+z)/(x+2y+3z)的值 快帮求
已知4x-3y-6z=0 ① ,x+2y-7z=0 ②,且x,y,z均不为0,求3x+2y+z÷x+2y+3z的值
若x:y:z=3:4:5且x+y+z=24,求x、y、z的值
若X:y:Z=3:4:5,且X+Y+Z=24,求X、Y、Z的值
已知x:y:z=2:3:4,且x-y+z=36,求x+y+z的值.
已知x:y:z=2:3:4,且x+y+z=18,求x,y,z的值
若4x-3y-6z=0,x+2y-7z=0且xyz≠0; 求(2x+3y+6z)/(x+5y+7z)的值?
若x/3=y/4=z/5,求x+y+z/3x-2y+z的值.