x^2+9y^2+4z^2-6xy-12yz+4xz=?Please,tell me the answer as fast as you could.I'm so sorry for I didn't tell you this.

已知实数x,y,z满足x=6-y,z^2-4z+4=xy-9,求x,y,z的值 已知实数x,y,z满足x=6-y,z^2-4z+4=xy-9,求x,y,z的值. 如果3y=x+2y,那么x *x+9*y*y+4*z*z-6xy-12yz+4xz的值是多少? 已知实数x,y,z,满足那么x+y=6,z^2=xy-9,求(x+y)^z x^2-4xy+4y^2-9z^2 12xy(2x+3y+4z)因式分解 化简2y-3z/2yz+2z-3x/3zx+9x-4y/6xy 若x/3=y=z/4,且xy+xz+yz=76,求2x*x+12y*y+9z*z的值 分解因式-6x^3y^2z+12x^2y^2z^2+18xy^2z^3 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x=6-y,z^2=xy-9,求证：x=y 已知有理数x,y,z满足x=6-y,z^2=xy-9,说明x=y 代数 x^-y^/ x^-(y-z)^ 除以 x^+2xy+y^/(x-y)^-z^ 乘 x^+xy-xz/x^-xy 1.x^2-9y^2/2x-6y 2.2x+6/x^+3x 3.x-2/x^2-4x+4 4.24xy^2z^3/4z^2y 5.-3xy·x/3y 因式分解30题(要过程)am+an+bm+bn x^2+5y-xy-5x x2+xy+2xz+x (a+b)x-(b+a)y -12x(x-y)-(y-x)x^2 2x^2+4x+2 x(x+z)-y(y+z) 2(x^2-3ab)+x(4a-3b) 4x^2+12xy+9y^2-25 x^4-16 16x^4-1 x^2+9x+8 x^2-10xy+24y^2 2x^2+15xy-8y^2 3x^2-6xy+3y^2 24x^2+22x-21 -x^2+4xy- -6xy乘3分之1x平方y的3次方z=,12xy(2x+3y+4z) 二元函数Z=x^2-xy+4y^2,求二阶偏导数Zxx Zxy Zyy