I want to solve :

```
    x2+x3=0
-x1   -x3=0
 x1-x2   =0

```

I got the $x\_1 = -t, x\_2=-t, x\_3=t$. But the book has $x\_1 = t, x2=t, x3=-t$.
Why don't we have the same answer? When I do Gaussian elimination I got this:

```
    x2+x3=0
 x1-x2   =0

```

Please help!