若|2X-4Y|+(Y+3Z)^2=0,则 2x-3y+5 /x-4y等于
若2x+5y+4z=0,3x+y-7z=0,则x+y-z的值等于( )
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
若2x+5y+4z=0 ,3x+y=0;则x+y-z=?
已知方程组4x-5y+2z=0 x+2y=3z 则x:y:z
2x+5y+4z=0,3x+y-7z=0,则x+y-z=?
4x-3y-6z=0,x+2y-7z=0是一个方程组,那么x-y+z/x+y+z的值等于
若2x+5y+4z=6,3x+y-7y=-4,则x+y-z等于多少
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-
2x+3y-4z=0.,3x+4y+5z=0,则x+y+z/x-y+z详细的解题过程
若4x-3y-6z=0,x+2y-7z=0,求代数式5x*5x+2y*2y-z*z/2x*2x-3y*3y-10z*10
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
若x比y比Z=2比5比7 则 2x+2y+z分之3x+4y-2z等于?