-- pick 2 points on the line -- find the change in 'y' as the line goes from one point to the other -- find the change in 'x' as the line goes from one point to the other -- divide (the change in y) by (the change in x). -- the quotient is the slope.
This is exactly the fraction in the picture, starting with "m = ".
For the line in the picture, let's take the starting point and the ending point.
-- the change in 'y' from beginning to end is 20 meters . -- the change in 'x' from beginning to end is 5 seconds .
