4/3x-2y+3/2x-5y=10 5/3x-2y-2/2x-5y=1 用换元法这个方程组用换元法解4/（3x-2y）+3/（2x-5y）=10① 5/（3x-2y）- 2/（2x-5y）= 1 ②

(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuaihuajian 5x^3y(x-y)^3-10x^4y^3(y-x)^2因式分解 5x^3y(x-y)^3-10x^4y^3(y-x)^2 5X^3Y(X-Y)-10X^4Y^3(Y-X)^2因式分解 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 先化简再求值(x-y)(x-2y)+(x-2y)(x-3y)-2(x-3y)(x-4y) x=4 y=5 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-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 3(2X+Y)+(2(2x-Y)=6 (8X+4y)-(10X-5Y)=2 (4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=? 4x-2*(10-x)-10=5y-3*(10-y)x+y=14 3X=5Y （X+Y)*3X=(2Y+X)*4+2*2 5/4(x+y)(-x-y)^3*[-4/3(x-y)]*[-3/5(y-x)^2] 化简(x+y)-(2x+y/2)-(3x+y/6)-(4x+y/12)-(5x+y/20)-……-(10x+y/90) x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2