(麻烦写出过程)1、y=3x-22、y=-1/x+13、√(x+3)4、y=2x/3x+15、y=x的指数(3/4) -
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
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
若x=-1/4,能否确定代数式(2x-y)(2x+y)+(2x-y)(y-4x)+2y(y-3x)的值?
{3(x+y)+3(y+x)=1,3(x+y)+4(y-x)=-1
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
{4/(x+y)+6/(x-y)=3 {9/(x-y)-1/(x+y)=1
化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1
已知2分之x+1=4分之y+3=5分之x+y,求x+2y+3分之3x+2y+1 写出过程
9y=3x-(x-1),4(x+y)-(2x+4)=8y
(3x-y)^2+(3x+y)(3x-y),x=1,y=-2
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