Solution for system of 2 equations of lines is coordinates of point at which those 2 lines intercept. The reason for is that those coordinates fit in both equations. IF you implement coordinates of that point in either of those equations of 2 lines you will see that left side is equal to right side which means that that point belongs to that line.
This method here is graphical method of solving system of equations. Other method is, of course, solving system of equations using math...
