Add drop lines at plot crossovers, swapping X and Y axis
 

Having some slight probs with a uni assignment. Basically, I need to swap the
x and y axis over, can't for the life of me work out how to do this as
everything I try seems to have no effect.
Secondly, there are four seperate plotted lines on the graph. I need to add
drop lines where a plot crosses another with a drop line marking the point on
the x and y axis. I will try get the graph up for y'all to see.