若x-2y=15,xy=-25,求x的平方加4y的平方减1

若1/x-1/y=2,求3x-2xy-3y/x-xy-y的值3x-2xy-3y/x-xy-y 不好意思，是3x-2xy-3y/x-2xy-y 若(y-x)/xy=3,求分式(2x+3xy-2y)/(x-2xy-y)的值 若x+y-5xy=0,求(2x-3xy+2y)/(x+2xy+y)的值 若xy=2（x+y),求 （3x-5xy+3y)÷(-x+3xy-y) 的值 若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值 若x+y=5,xy=6,求x^2y+xy^2的值 若X+Y=0,XY=11,求X^2-XY+Y^2的值. 若x,y满足x^+2y^-2xy+1=0,求xy的值 若正实数x,y满足2x+y+6=xy,求xy的最小值. 若正实数X,Y满足2X+Y+6=XY,求XY的最小值. 如果x^2+xy+y-14,y^@+xy+x=28,求x+y的值. 若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*y)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? 若正整数X,Y满足2X+Y--XY=0,求X+Y的最小值 若x^2+xy+y=14,y^2+xy+x=28,求x+y x-2y=15,xy=-25,求x*x+4y*y-1 若x+y=4 x-y=6 求xy(x^2+y)-y^2(xy+2x)-3xy的值求值