已知x、y、z满足x—2y+z=0 7x+4y—5z=0 ,求x：y：z

已知x、y、z满足x—2y+z=0 7x+4y—5z=0 ,求x：y：z 已知x,y,z,满足方程组x-2y+z=0,7x+4y-5z=0 已知x、y、z满足方程组：x+y-z=6；y+z-x=2；z+x-y=0 求x、y、z的值 已知X.Y.Z满足方程组,X+y-Z=6y+z-x=2z+x-y=0求X.Y.Z的值 已知x.y.z满足x-2y+z=0且7x+4y-5z=0,求x:y:z的值 已知x,y,z满足方程组x-2y+z=0 7x+4y-5z=0求x:y:z的值 已知有理数x、y、z满足条件|x-z-2|+(3x-6y-7)^2+|3y+3z-4|=0,求x、y、z 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满足{x-2y+z=0;7x+4x-5z=0,求x:y:z的值. 已知x,y,z满足方程组｛x+y-z=6{y+z-x=2{z+x_y=0,求x,y,z的值 已知z不等于0,x、y、z满足4x-7y-5x=0,2x-y-z=0.求x：y 已知z、y、z同时满足x+3y-5z=0,2x-y-3z=0,求x:y:z 已知x,y,z满足方程组x-2y+z=0 7x+4y-5z=0,且z不等于0,2x²-3y²+z²/y²-2z²的值为? 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 已知：x^2/(z+y)+y^2/(x+z)+z^2/(x+y)=0,求x/(z+y)+y/(x+z)+z/(x+y)的值. 已知X,Y,Z满足X-2Y+Z等于0,7X+4Y-5Z等于0,求X比Y比Z 已知X,Y,Z满足X-2Y+Z等于0,7X+4Y-5Z等于0,求X比Y比Z