已知x+3y=6,x+3y-2xy+2z^2=0,求x^(2y+z)已知x+y-2是多项式x^2+axy+by^2-5x+y+6的一个因式,求a,b的值.如果（x-a)(x-4)-1能够分解成两个多项式（x+b)与（x+c)的积（b,c为整数）,求a

已知4x-3y=6z 2x+4y=14z 求2xy/x^+y^ 已知4x-3y=6z 2x+4y=14z 求2xy/x^+y^ 已知实数x .y.z.满足2^x=3^y=6^z 求证:xy+yz=xz 已知3x－y+2z=x+2y+3z=0,求（3x^－xy+2y^)/(2x^+4xy+y^)值? 已知实数x,y,z满足x+3y=6,2xy-z^2=6,求x、y、z的值 已知xy/x+y=2/3,yz/y+z=6/5.xz/x+z=3/4求x-z^y 已知XY+X/X+Y+1=2 XZ+2X/X+Z+2=3 (Y+1)(Z+2)/Y+Z+3=4 求X+Y+Z的值已知(XY+X)/(X+Y+1)=2 (XZ+2X)/(X+Z+2)=3 [(Y+1)(Z+2)]/(Y+Z+3)=4 求X+Y+Z的值 已知（x+y-xy）/(x+y+2xy)=(y+z-2yz)/(y+z+3yz)=(z+x-3zx)/(z+x+4zx),且2/x=3/y-1/z,则xyz=? 已知实数x,y,z,满足那么x+y=6,z^2=xy-9,求(x+y)^z 已知xy/x+y=3,yz/y+z=2,zx/z+x=1,求y的值 1'已知x^2-3y^2=2xy(x>0,y>0)那么x-y分之x+2y的值是?2'已知x^2+y^2+z^2-4x-6y-12z 已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z 已知2x-3y-z=0,x+3y-14z=0(z≠0),求x^2+3xy／y^2+z^2 已知(3x+2z)/4=(3y+z)/5=(5x+y-z)/6,求x*x-2xy+y*y与(-2z)(-2z)的比值. 已知2x-3y-z=0 x+3y-14z=0(z≠0) 求x^+3xy/y^2+z^ 已知,xy/(x+y)=1,zy/(z+y)=2,zx/(x+z)=3,球x=? 已知xy/(x+y)=1,yz/(y+z)=2,zx/(z+x)=3,求x的值 已知1=xy/x+y,2=yz/y+z,3=xz/x+z,求 X的值