Question 74438
Use this solver.

http://www.algebra.com/tutors/calculating_slope.solver?content_action=show_dev

 Plug in the 2 points ({{{x[1]}}},{{{y[1]}}}) and ({{{x[2]}}},{{{y[2]}}}) and it will use the slope formula to explain how it got the answer. It will not only give you the slope (in m= form) but it will give  you the equation of the line also.