We want to reduce as many variable as we can so, we can obtain the value for the remaining variables.
Therefore, the first equation y=x+5 multiply it -2., you have -2y=-2x-10 and sum it to the second (2y-x=13), you will obtain the following: -x=13-2x-10.
You have x=3.
If you substitute x=3 in the first equation, you have y=8
