2X=18-3Y=26-5Y X=?Y=?

x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) （x+y-5)*（x+y-5)+（x-y+3)=0 x*x-y*y 已知:3x-5y=0,求x/y,x-y/y,x-y/x x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5 (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 先化简再求值(x-y)(x-2y)+(x-2y)(x-3y)-2(x-3y)(x-4y) x=4 y=5 计算题!【x+y+z=26；x-y=1；2x-y+z=18】!【x/3+y/5；x/2-2y/5=1】 (x+y)(x-y)+(x-y)平方-(x-y)(3x-y) 其中x=-2 y=3分之一 (x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)= {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? (x+y)(2x-3y)=? 化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1 2X=18-3Y=26-5Y X=?Y=?