-6x(2/3x-2/5y)+12y(-3/8x+1/3y)=?
【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2=
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y
6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
x^8-x^7y+x^6y^2-x^5y^3+x^4y^4-x^3y^5+x^2y^-xy^7+y^8
化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1
因式分解 (1)6(x-y)^3-3y(y-x)^2 (2)x(x-y)(a-b)-y(y-x)(
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
x+y=3 x+2y=9 3/x+1=y y-x=3 y=2x-3 y-3x=1 2(x+1)-y=6 7x-5y=-9
x+y/2+x-y/3=5/6;x=y/6-x-y/3=1/2
解方程组:x+y/2+x-y/3=6 4(x+y)-5(x-y)=12