若|3x-1|+(2y+1)2=0,求2x2+3y2/x-y的值

若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 若(x+y)(x+y-1)-2=0,求x+y的值求 求导数y=3x-x^2 求y',y'/ x=1 y'/x=0 若(2x-y-1)2+|x-2y-3|=0,求代数式(2x+y)(2x-y)-(x+2y)(x-2y-1)的值若(2x-y-1)²+|x-2y-3|=0,求代数式(2x+y)(2x-y)-(x+2y)(x-2y-1)的值 若x*x+y*y=x+y-1/2,求x,y的值如题 (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 若|x+y-1|+（x-y-2)²=0,求代数式（x+2y)(x-2y）-（2x-y)(-y-2x)的值. 若x-y=3,x^2-y^2=1,求x+y的值 3x+4y-5=0 x^2+y^2=1求x.y 若|x-1|+|2x+4y|=0,求3x-2y 已知|2x-3y|+|3x-y-1|=0,求x,y的值. 若x^5+x^4y+x^4+x+y+1=0,且3x+2y=1,求x,y的值 若x-y=2(x+y),求代数式x-y/x+y+x+y/x-y求代数式 x+y分之x-y+x-y分之x+y 已知:y=ax的3次方+bx+3,当x=-1/2时,y=-7,试求x=1/2时,y的值 已知X,Y满足|X-Y-1|+（X+Y-3)^2=0求X,Y的值 {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? 若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值 x²-4x-1=0,求(2x-3)²-(x+y)(x-y)-y² 若|3y-2x-5|+(3x+4y-1)^2=0,求x+y