{x+3y/2=3/5 {5(x-2y)=-4

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/6=5 2(x+y)-3(x-y)=-2 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 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 先化简再求值(x-y)(x-2y)+(x-2y)(x-3y)-2(x-3y)(x-4y) x=4 y=5 化简:5(x-y)+2(x+y)-3(x-y) {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? (2x-3y)-(5x-y) (2X-3y)-(5x-y) (2x-5y)(3x+y) 因式分解(x-2y)(x-3y)+(x-4y)(x-5y)+（x-3y)(x-5y)+(x-2y)(x-4y) 化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1 (2x+y)²+(x+3y)(x-3y)-x(5x+8y)因式分解 [2(x-y)^5-8(x-y)^2(x+y)+6y(x-y)^2]÷2(x-y)^2[2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2]÷2(x-y)^2 (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuaihuajian