求3x-2y=1,2x+3y=-8的解

若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 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 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 y=3(x-y),x=2(x-y)求x,y的值 (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 1奥数题x-2y/x+2y=3,求x-2y/3(x+2y)-3(x-2y)/x-2y的差 分式加减的几道题目求速度1 .(x+y)²/（x-z)(y-z) - (y+z)²/（x-z)(y-z) = 2.2x+3y/x-y+2y/y-x-3y/x-y= 已知(3x+1)(3x-3)-3x+2)^2=-7,(y+7)(y-7)-y(y-7)=0,求8y^2-5y(-y+3x)+4y(-4y-5/2x)的值 {(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 求5x-2y=x-y=4x-3y-2的解 解方程组：｛x：y=3：2 x-y=16求x、y的值 -2x+3y=3x-2y+1求x.y的大小关系 若x-y=3,x^2-y^2=1,求x+y的值 已知X-Y=3,求X-Y的2次幂减3X+3Y+1 已知|2x-3y|+|3x-y-1|=0,求x,y的值. 3x=2y+1;x=9y;求x,y的值?