x+y=27 y+z=33 x+z+=30 解出来

(x+y-z)(x-y+z)= X+Y+Z=? 解方程组{x(x+y+z)=6,y(x+y+z)=12,z(x+y+z)=18 f(x,y,z,w)=x*(x+y)*(x+y+z)*(x+y+z+w) 解三元一次方程组,100x+10y+z=27(x+y+z) {x+y-z=1 (100z+10y+x)-(100x+10 设X,Y,Z都是整数,满足条件(X-Y)(Y-Z)(Z-X)=X+Y+Z,试证明X+Y+Z能被27整除 x*(y-Z)=27,y*(x-Z)=35,Z*(x+y)=28三个方程正整数解 x y z x+y--- = --- = ---- ----y+Z z+x x+y ,求 z 的值 .求 x+y---- 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