Find the value of r in (4 , r), (r , 2) so that the slope of the line containing them is -5/3.

Suppose you are analyzing the relationship between time and distance given in a table, and there are 4 values for each quantity. you divide distance 2 minus distance 1 by time 2 minus time 1.you then divide distance 4 minus distance 3 by time 4 minus time 3 and get a different answer. what can you say about the relationship?