⑴1/2x+3y=2/3 x-3/4y=-29/12 ⑵2x+3y=8 3x+4y=11 (^_-)-☆
3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
9y=3x-(x-1),4(x+y)-(2x+4)=8y
化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1
x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20
{(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20
4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6
(x+y)(x+2y)(x+3y)(x+4y)=-40
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
【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)]=? kuai
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