已知-4x+3y-13+(y-3)^2=0,则x·y=

已知2y-x=-3,求[4y(2x-y)-2x(2x-y)]/(2x-y 已知-4x+3y-13+(y-3)^2=0,则x·y= 化简求值：已知x、y满足：x^2+y^2-4x+6y+13=0 求代数式 的值.(3x+y)^2-3(3x-y)(x+y)-(x-3y)(x+3y)急用！ 已知x-y=1,求[(x+2y)^2+(2x+y)(x-4y)-3(x+y)(x-y)]除以y的值大神们帮帮忙 已知(x+2y)(2x-3y)=y(y-4x),试求x/y的值 已知x-y=1,求[(x+2y)²+(2x+y)(x-4y)-3(x+y)(x-y)]÷y的值 已知(x-y)/13=y/7,则（x+y）/y=已知x/6=y/4=z/3(x,y,z均不为零）,则(x+3y)/(3y-2z)= 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 已知x²+4y+y²—6y+13=0,求2x+3y的值 已知x=3分之一,y=-2分之一,求代数式x-(x+y)+(x+2Y)-(x+3y)+(x+4y)...-(x+2009y) 已知x、y满足x2+y2-4x+6y+13=0 求代数式（3x+y)2-3(3x-y)(x+y)-(x-3y)(x+3y)已知x、y满足x^2+y^2-4x+6y+13=0 求代数式（3x+y)^2-3(3x-y)(x+y)-(x-3y)(x+3y)的值 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 已知3x =2y 求x/x+y+y/x-y-y²/x²-y² 已知（x+y）2 =2,(x-y)3 =3,求(x+y)7(x-y)2(x+y)3(y-x)4 的值 已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y除以2x-y 已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y/2x-y的值 已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y/2x-y的值 已知实数x.y满足根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-2y+7),求x,y