Each shows two lines that make up a system of equations. If the graphs of the equations intersect, then there is one solution that is true for both equations. If the graphs of the equations do not intersect (for example, if they are parallel), then there are no solutions that are true for both equations.
Maybe try dividing by 300 and timesing by 1000?
Slope = (y2 - y1)/(x2 - x1)
slope = (-3 -4)/(1 - 1)
slope -7/0
This is an undefined slope because the denominator is 0.
This would be a vertical line.
