Answer:
M = (Y2 - Y1) / (X2 - X1)
Step-by-step explanation:
First, look at a graph of a line and find two points, 1 and 2. You can use any two points on a line. The slope will be the same between any two points on a straight line.
Note the X and Y value for each of the points.
Now we'll designate the X and Y value for points 1 and 2. We'll use subscripts to identify them in the slope formula.
Hope this helps!