如果x/3=y/2=z/5,求(2x+3xy-2y)/(x-y+z)的值

已知实数x,y,z满足x-y=5,z^2=-xy-y-9,求x-2y+3z的值 已知实数x,y,z,满足x+y=5,z²=xy+y=9,求x+2y+3Z的值 已知x y z 满足x+y=5,z²=xy+y-9,求x+2y+3z的值 若x-y=6,xy=-8,求代数式(x+y+z)²+(x-y-z)(x-y+z)-2·z(x+y)的值 如果1=xy/x+y,2=yz/y+z,3=xz/x+z,则x的值? 如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y, 若x/3=y/2=z/5,且xy+yz+zx=93,求9x*x+12y*y+2z*z的值. 已知xy/x+y=3,yz/y+z=2,zx/z+x=1,求y的值 x/3=y/4=z/5,求x+y+z/3x-2y+z的值, 若x/3=y/4=z/5,求x+y+z/3x-2y+z的值. x+2y+3z=20,x+3y+5z=31,求x+y+z的值 已知x/4=y/5=z/6 求x+y+z/3x-2y+z的值