（x+y）/2- x-y/2=6 3(x+y)=4(x-y)

（x+y）/2- x-y/2=6 3(x+y)=4(x-y) 【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2= x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2 x+y/3+x-y/2=6 4(x+y)-2(x-y)=40 （y-x）^4（x-y）^3+2（x-y）^6（y-x） x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20 {(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20 4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6 2(x+y)-3(x-y)=1 6(x+y)+(x-y)=51 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 把6x（x－y）的平方＋3（y－x）的立方分解因式我知道答案是6x(x-y)^2+3(y-x)^3=6x(x-y)^2-3(x-y)^3=3(x-y)^2[2x-(x-y)]=3(x-y)^2(x+y)可为什么=6x(x-y)^2-3(x-y)^3=3(x-y)^2[2x-(x-y)] x+y/2+ x-y/2=6 2(x+y)-3x+3y=24 求X Y 2（x-y）²-3(x-y)(-y-x) 3x+y=2 -y/x+y=123x+y=2 （-y/x）+y=12 如果A={（x,y）|x,y+2>0},B={（x,y）|2x+3y-6>0},C={（x,y）|x-4