The graph at the right shows four different direct variation equations plotted on the same coordinate grid. using what you know about direct variation, calculate the constant of proportionality (k-value) of each relationship and match it to a point on each line. choose from the k-values listed below. some may not be used.

k = -1
k = -9/2
k = 2/9
k = -1/5
k = 1/5
k = 3
k = -2
k = 1

point a __
point b __
point c __
point d __