A. Slope Facts
 Positive slope – when the line slants upward from left to right.
 Negative slope – when the line slants downward from left to right.
 There are two directions or changes with slope.
 The up and down change or vertical change is the change in the yvalues.
 The left and right change or horizontal change is the change in the xvalues.
 The slope formula is m = (y_{2}  y_{1}) / (x_{2}  x_{1}) and used when you know two points on the line.
 Label the points (x_{1}, y_{1}) & (x_{2}, y_{2}).
 Substitute the numbers into the formula.
 Perform the operation in the numerator and denominator.
 Reduce the fraction completely.
 DO NOT write slope as a mixed number.
 A horizontal line with equation y = # has a slope of zero.
 The yvalues would be the same therefore zero would be obtained in the numerator of the formula.
 Zero divided by any number equals zero.
 A vertical line with equation x = # has no slope or undefined slope.
 The xvalues would be the same therefore zero would be obtained in the denominator of the formula.
 Any number divided by zero is undefined.


B. How to Determine the Slope of a Graphed Line Using (rise)/(run)
 Pick any two points on the line.
 Determine the rise by counting the spaces you move up or down.
 Move up – positive number
 Move down – negative number
 Determine the run by counting the spaces you move right or left.
 Move right – positive number
 Move left – negative number
C. How to Graph a Line with a Given Slope and a Given Point the Line Goes Through
 Graph the given point.
 Use the movements of slope (or rise/run) from the graphed point.
 Make a point after making the two movements and repeat to graph more points.


