2x^2+6xy+9y^2-6x+9=0,求x,y的值.

(x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)答案应为-2x-x*x-3x， 已知x^2-6xy+9y^2=0,求(x-y)/(x+y) 化简：x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y) 2x方-6xy+9y方-4x+4=0 xy=多少 3x的平方-xy/9x的平方-6xy+y的平方,其中2x-y=0 已知x^2+9y^2-2x-6y+2=0,求{-（xy/（x-y）^2}^4*(y^2-xy/x)^3*x^4/y^10/(x/xy-y^2)^5的值 -3x^2y+6xy^2-9xy=( )(x-2y+3) 若2x^2-6xy+9y^2-4x+4=0,则y/x-x/y=若2x^2-6xy+9y^2-4x+4=0,则y/x-x/y=? 求x^3 - 6x^2y + 11xy^2 - 6y^3 思路x^3 - 6x^2y + 11xy^2 - 6y^3= x^3 - 3x^2y + 2xy^2 - 3x^2y + 9xy^2 - 6y^3= (x^2 - 3xy + 2y^2)(x - 3y)= (x^2 - 2xy - xy + 2y^2)(x - 3y)(x - y)(x - 2y)(x - 3y)求思路 x^2-4xy+5y^2+6y+9=0,x+y= 3x^2-xy /9x^2-6xy+y^2=x/( )=( )/9x^2-y^2 3/x —2/y=3 (2x-3y-xy) / (7xy+9y-6x)= -9y^2+6xy-x^2 (9x^2y-6xy^2)/3xy [ 2x-6y][8-9xy]÷xy等于? 已知x+y=2xy,且xy不等于0,则求-2x+6xy-2y/(7x+5y)-9xy-(3x+y)=___ 化简求值,若X方-2XY+Y方+1XY-11=0,求X方+6XY+9Y方分之X方-25Y方*5X-25Y分之X+3Y的值 解方程组：{x²+xy-2y²=0,x²+6xy-9y²=1