Question 713824
This is a pretty simple problem if you know how to substitute problems.  
    The answer to this problem is:  
                               x=-1
                               y=0
Here's the work:
             2x+y-(-x)-y=-2-1
                2x+x+y-y=-3
                        3x=-3
                          x=-1
Then you substitute x into equation 1:
             -(-1)+y=1
                     y=1-(-(-1))
                     y=1-1
                     y=0
I hope you understand my work and explanation, you can email me if you have any more questions! Enjoy!     ;)