若2x-y=-1,3x-2y=3,求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 (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? 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 若x-y=3,x^2-y^2=1,求x+y的值 已知：2x+y=6,x-3y=1 求7y(x-3y)(x-3y)-2(3y-x)(3y-x) 已知x-y=1,求[(x+2y)^2+(2x+y)(x-4y)-3(x+y)(x-y)]除以y的值大神们帮帮忙 已知x-y=1,求[(x+2y)²+(2x+y)(x-4y)-3(x+y)(x-y)]÷y的值 若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 已知3x =2y 求x/x+y+y/x-y-y²/x²-y² 已知|x|=2,|y|=3,|x+y|=-(x+y)求x-y 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 y=3(x-y),x=2(x-y)求x,y的值 1奥数题x-2y/x+2y=3,求x-2y/3(x+2y)-3(x-2y)/x-2y的差 若x-y/x+y=5,求x-y/2x+2y+5x+5y/3x-3y的值