Answer:

Explanation:
To find the slope of a straight line only two known points on the straight line are sufficient.
If we take the first two points i.e. (-1,3) and (2,-1), then slope of the straight line will be
(Answer)
Note: Since we know that if a straight line passes through two points (x1,y1) and (x2,y2), then the slope of the straight line is given by