已知x:y=5:3,x:z=7:3,2x-y-z=34,求三个未知数的值
已知x+4y+3z=3x-2y-5z=0,求x+2y-z/2x-3y+7z的值
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.
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.
已知x+y-z=0,2x-y+2z=0 求(3x-2y+5z)/(5x-3y+2z)的值
已知x,y,z满足3x+7y+z=5 4x+10y+z=3 求x+y+z的值
已知x、y、z满足{3x+7y+z=5 ,求x+y+z的值 {4x+10y+z=3
已知有理数x,y,z满足|x-z-2|+|3x-6y-7|+(3y+3z-40)^2=0,求x,y,z的值
已知x,y,z,同时满足方程x+3y-5z=0,2x-y-3z=0求x:y:z的值
已知{3x+4y+5z=0,2x+3y-4z=0,求x+y+z/x-y+z的值.
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/x-y+z的值.