3x=4(x-y) x-8(x-y)=5

(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai （5x+3y)(3y-5x)-(4x-y)(4y+x)= 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 x-y+5x-4x= ? y=(x-1)(x-2)(x-3)(x-4)(x-5)(x-6)(x-7)(x-8)(x-9)(x-10)的导数在x=1 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 3x=4(x-y) x-8(x-y)=5 解下列方程组 3x=4(x-y) x-8(x-y)=5 已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-( 数学题……555{(3x+y)(3x-y)-(x-5y)(5x-y)-(x-2y)²÷(-4x),x=-2.y 方程组x-2y=8,3x-4y=5,x=?,y=? 化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1