已知x/3=y/4=z/5 求 分式y^2+z^2-x^2/x^2+z^2-y^2
已知x:y:z=3:4:5,3x+2y-4z=18.求:x+y+z.
已知2x+5y+4z=6 3x+y-7z=-4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.
已知3x=4y,2y=5z,试求x:y:z
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+4y+3z=3x-2y-5z=0,求x+2y-z/2x-3y+7z的值
已知2x+3y-4z=0,3x+4y-5z=0.求x+y+z除以x-y+z,
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.
已知3x+4y+5z=0,2x+3y-4z=0,求(x+y+z)/(x-y+z)