x^+y^-6x-8y+25=0.求xy

已知x的平方+y的平方-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y) 已知x²+y²-8x+6y+25=0,求（x-y+4xy/x-y）（x+y-4xy/x+y） x^+y^-6x-8y+25=0.求xy 诺x+y=6,xy=4 求(5x-4y-3xy)-(8x-y+2xy) x+y=6,xy=8,求5x+xy+5y/x-xy+y的值 已知x.x+y.y+8x+6y+25=0,求代数式(x.x-4y.y)/(x.x+4xy+4y.y)-x/(x+2y)的值 帮个忙啦 已知x+y=-6 xy=8 求√y/x+√x/y 已知(1/x)-(1/y)=5,求(6x+7xy-6y)/(8y-9xy-8y) 已知:x²-6x+8y+y²+25=0,求x²+2xy+y² 已知1/X^2 +1/Y^2 -6/X -8/Y +25=0求X+Y/XY的值 已知x的平方+y的平方-8x+6y+25=0,求【x-y+x-y分之4xy】乘【x+y-x+y分之4xy】的值 已知x的平方+y的平方-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)的值 x^2+y^2-6x-8y+25=o 求代数式(xy-3x^2)/ y^2-xy-6x^2 的值 已知x-xy=8,xy-y=-9,求x+y-2xy的值 1-2/x+y=xy,4y+6x=xy.求xy的解? x+y=8,xy=-2,求(5xy+4x+7y)+(6x-3xy)-(4xy-3y)的值 已知x+y=6,xy=7,试求x*x+y*y,x*x-y*y的值 已知xy=-2,x-y=3,求（x+y)（x-y)-y^2+（x-y)^2-（6x^2y-2xy^2)÷2y