Calculate Slope With a Formula
Measure slope, –m, with the following formula:
m= y21 x2−x1
Be careful: x and y are not raised to the 2nd power.
Calculate the slope of y= 1/2x +2 using the following points on the graph: (2,3) and (-8,-2).
Follow these steps:
1. Label x1, y1,x2, y2:
x1,y1 x2,y2
(2,3) (-8,-2)
2. Plug the numbers into the formula:
m= -2−3
-8−2
3. Simplify:
m= -5
-10
m= 1
2
Slope is 1/2.
Notice that the slope is the same here as it was when we used points A and B on the graph. For any given linear function, the slope is the same throughout the entire line.
