All four of these lines intersect at one point. According to the graph, all points intersect at (0,3) where the x coordinate is zero and y is the point where all 4 lines intersect (y=3) because if you put x=0, the y coordinate for all four equations will be 3. So point (0,3) is where all four lines intersect.
The numbers in front of each of the "x"s, (2, 4, -2, -4) are the SLOPES. If the number in front of the x is positive, it has a positive slope (line is inclining, going up), if the number in front of the x is negative, then it has a negative slope (line is declining, going down).
Remember line equation is:
y = mx + b, where m=slope, b=constant, x=x coordinate, y= answer you get when you plug in x coordinate.
Let me know if you have any more questions about this.