x,y,z不是0.3z=4y,z=3x求(x+y):(x+z).
x分之y+z=y分之z+x=z分之x+y(x+y+z不等于0),求x+y+z分之x+y-z
已知x::y:z=3:4:5,(1)求x+y分之z的值;(2)若x+y+z=6,求x,y,z.
(x+y-z)(x-y+z)=
已知2x+3y-4z=0,3x+4y+5z=0,求x+y+z/(除以)x-y+z的值.
1.设X ,Y,Z 成等差数列,代数式(X-Z)*(X-Z)+ 4(X-Y)(Z-Y)=
已知3x-2y-5z=0,2x-5y+4z=0,且x,y,z都不为0,求(3x*x+y*y+4z*z)/(5x*x+y*
已知x,y,z满足{4x-3y-3z=0,x-3y+z=0.(x不等于0,y不等于0,z不等于0)求x/z和y/z的值
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
1.已知x:y:z=4:5:7,求:(一)2x+3y+z/5z; (二)x+y/y+z 非常急,
已知x/2=y/3=z/4,求下列各式 (1)(x+y+z)/x (2)(x-y+2x/(x-y-2z)
x y z x+y--- = --- = ---- ----y+Z z+x x+y ,求 z 的值 .求 x+y----
(x+y+z)*(-x+y+z)*(x-y+z)*(x+y-z)=