已知X/2=Y/3=Z/4≠0,求2x+3y-z/x+2y-3z
已知方程组2x-3y-4z=0和x+y+z=0,并且z≠0,求x:y与y:z
已知x+4y+3z=3x-2y-5z=0,求x+2y-z/2x-3y+7z的值
已知x/2=y/3=z/4,且x+y+z不等于0,求2x+3y-4z/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{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)
已知4x-3y+z=0,x+2y-8z=0,xyz不等于0,求x+y-z/x-y+2z的值
已知2x+3y-4z=0,3x+4y-5z=0.求x+y+z除以x-y+z,
已知3x-2y-5z=0,2x-5y+4z=0,且x,y,z均不为0,求3x*x+2y*y+5z*z/5x*x+y*y-
已知x,y,z 大于0,x+y+z=2,求证 xz/y(y+z)+zy/x(x+y)+yx/z(z+x)大于等于2/3