已知{3x+2y=17,2x+3y=13,则x-y=

已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 已知,{3x+2y=17 2x+3y=13,则x+y= x-y= 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|=2,|y|=3,|x+y|=-(x+y)求x-y 已知2y-x=-3,求[4y(2x-y)-2x(2x-y)]/(2x-y 已知2x=3y,则y分之x=< >,y分之x+y=< >. 已知：2x+y=6,x-3y=1 求7y(x-3y)(x-3y)-2(3y-x)(3y-x) 已知x=3分之1,y=二分之一,求代数式x-(x+y）+（x+2y)-(x+3y)+...-(x+13y)的值 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-y=1,求[(x+2y)²+(2x+y)(x-4y)-3(x+y)(x-y)]÷y的值 已知x、y均为实数,且满足xy+x+y=17,x^2y+y^2x=66,求x^4+x^3y+x^2*y^2+y^3x+y^4的值 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+2y)(2x-3y)=y(y-4x),试求x/y的值 已知|x+y-3|+(x-y)2=0则 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{3x+2y=17,2x+3y=13,则x-y= 已知x-3y=0,求(2x+y)/(x^2-2xy+y^2)X(x-y)