xy≠1,5x^2+2001x+9=0,9y^2+2001y+5=0,求x/y的值

已知(x+1)²+|y-1|=0,求2(xy-5xy²)-(3xy²-xy)得值 若（x+1)^2+|y-2|=0,求3x^2-[5xy-(x^2y-3xy)+4x^2y-8xy]的值 xy≠1,5x^2+2001x+9=0,9y^2+2001y+5=0,求x/y的值 1.xy-3x=40;x=52.7x-xy=-18;x=-63.3xy-28=16x;x=44.9y+6xy=30;x=-65.y-2xy=15;x=-16.4x+7y+5xy=0;x=1 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 已知13X^2-6XY+Y^2-4X+1=0,求(XY-X^2)^5的值. 已知（x+1）*（x+1）=-Iy-1I,求2（xy-（5xy）*（5xy））-3（（xy）*（xy）-xy） 已知X-XY-2Y=0求2X+3XY-Y/X-2XY+5Y 若x+y-5xy=0,求(2x-3xy+2y)/(x+2xy+y)的值 (8xy-3x平方)-5xy-2(3xy-2x平方),其中,x=2,y=-1 已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y= 问几道有关分式的数学题 ,(1)[(5xy)/(x²+xy)]*[(xy+y²)/(2x²y²)]^3(2)[(x^3-3x+4)/(x²+2x-3)]÷[(x²-16)/(x²+6x+9)](3)(x²+x-3)/(x²+x-2)+1=(2x²+4x+1)/(x²+2x+1)(4)已知a²+4a+1=0 ,且(a^4+ 已知x-y=3xy,且xy不等于0,则-3x+6xy+3y/(7x-5y)-9xy-(3x-y) 若x-y=4,xy=1,则(2x+y-2xy)-(3x+2y+xy)-(4xy+3y-5x)= (-2xy+2x+5y)-(3xy+2y-2x)-(x+4y+xy)其中x-y=4xy=-1 已知13x^2-6xy+y^2-4x+1=0,求(x^2-xy)^5的值特别注意是求(x^2-xy)^5的值,不是（xy-x^2）^5的值 已知A=2x^2+3xy-2x-1,B=-x^2+xy-1,且3A+6B的值与x无关,求y的值3A+6B =3（2X^2+3XY-2X-1）+6（-X^2+XY-1）=6x^2+9xy-6x-3-6x^2+6xy-6 =15xy-6x-9 =x(15y-6)-9 与x无关 则x前系数 =0 15y-6=0 y=2/5但倒数第5行上的-9去哪里了 已知（x+2)^2+|y+1|=0,求5xy^2-{2x^2y-[3xy^2-(4xy^2-2x^2y)]}