x+y=20 x-y=4 z-x+y=10
(x+y-z)(x-y+z)=
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
X+Y+Z=?
f(x,y,z,w)=x*(x+y)*(x+y+z)*(x+y+z+w)
若{x+3y+10z=0 则 (x+y-z)/(x-y+z)
x y z x+y--- = --- = ---- ----y+Z z+x x+y ,求 z 的值 .求 x+y----
2X+Y+Z=10,X+2Y+Z=-6,X+Y+2Z=8 5X+4Y-3Y=13,2X-3Y+7Z=19,3X-Y=2X
已知x+y-z/z=x-y+z/y=-x+y+z/x,且xyz不等于0,求分式[(x+y)(x+z)(y+z)]/xyz
若z分之x+y+z=y分之x-y+z=x分之-x+y+z,求xyz分之(x+y)(y+z)(z+x)
y+z÷x=Z+X÷y=X+Y÷z,X+Y+Z不等0求X+Y-Z÷X+Y+z值
(x+y-z)/z=(y+z-x)/x=(z+x-y)/y 求(x+y)(y+z)(z+x)/xyz
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