The Slope of a Line
The slope of a line is a measure of its steepness. The steeper the line, the higher the absolute value of the slope.
The figure below shows some lines and we can see they have different slopes:
The red line has a positive relative small slope. The green line has a positive higher slope, the blue line has the highest positive slope.
The purple line has a negative slope.
The slope is usually calculated as the rise over run formula:
Where rise is the change of the value of y and run is the change of the value of x.
For example, the line that passes through the points (2, -3) and (5, 6) has a rise of 6 - (-3) = 9 and a run of 5 - 2 = 3.
Thus the slope is: m = 9/3 = 3