急··已知x/3=y/5=z/7,求(x+z-y)/y和(2x+3y+4z)/(5x-3y+z)
已知x/3=y/5=z/4,求x+y+z/y和x+y-z/y-x的值,2种方法.急等.
1.已知x:y:z=4:5:7,求:(一)2x+3y+z/5z; (二)x+y/y+z 非常急,
急··已知x/3=y/5=z/7,求(x+z-y)/y和(2x+3y+4z)/(5x-3y+z)
已知2x+5y+4z=6 3x+y-7z=-4求x+y-z
已知x+4y+3z=3x-2y-5z=0,求x+2y-z/2x-3y+7z的值
已知5x=3y,4z=7y,求x:y:z
已知3x=4y,2y=5z,试求x:y:z
已知x:y:z=4:5:7,求:(1)2x+3y+z/5z; (2)x+y/y+z.
已知x:y:z=3:4:5,3x+2y-4z=18.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=4X,5Y=6Z求X+Y:Y+Z