若9x^2+24x+y^2_6y+25=0,则xy的值为 A-6 B-4 C4 D6

若9x^2+24x+y^2_6y+25=0,则xy的值为 A-6 B-4 C4 D6 x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 若9x^2+y^2+24x-6y+25=0,则xy= 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 若2x=3y,则(x*x+y*y)/x*x=? 若2x+3y=2004,则代数式2(3x-2y)-(x-y)+(-x+9y)=... 若2x+y=2012,则代数式2(3x-2y)-(x-y)+(-x+9y)= 若x^2+y^2-6x+8y+25=0 则y/x-x/y的值是 若f(x+y,y/x)=x^2-y^2,则F(X,Y)= 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 3(x+y)-2(x-y)=11 4(x+y)+3(x-y)=9 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 若x*x+y*y=x+y-1/2,求x,y的值如题 若x-y=6,x^2-y^2=24,则x+y=? 若方程组x+2y=6,2x+y=9 那么x+y=? 若x-y=9,则X^2+y^2=91,x*y=? 若／X+Y-9／+（2X-Y+3)=0求X与Y的值 若x^2+9y^2-2x+24y+17=0,求x^2与y^2