which formula can be used to find the slope of a line from two points (x1, y1) and (x2, y2)

x2-x1/y2-y1
y2+y1/x2+x1
y2-y2/x2-x1
y2/y1-x2/x1

The formula that can be used to find the slope of a line from two points (x1, y1) and (x2, y2) is:

(y2 - y1) / (x2 - x1)