Question 43370
gradient = (change in y)/(change in x)


so either:
gradient = (6-2)/(-1-5)
--> gradient = 4/-6
--> gradient = -2/3


or gradient = (2-6)/(5--1)
--> gradient = -4/6
--> gradient = -2/3


As you can see, it does not matter which way round you have the 2 sets of coordinates. Just never mix them up.


jon