How do we determine the slope of a line given a graph?
Given a graph,
we can determine the slope by looking at the horizontal distance between the points "rise" divided by the vertical distance between the points "run". In other words,
Now, when we look at a graph and use the slope formula "rise over run", we need to think about the direction that we are moving in! For example,
On a graph, if you move up then this is a positive distance. In comparison, if you move down then this is a negative distance. The same is true when you move left or right. If you move left then this is a negative distance. Lastly, if you move right then this is a positive distance.
Example
Given the following graph, determine the slope:
Note - I could have started from the top point, however I find it easier for me to always start from the bottom point. Either way, you should always get the same answer for the slope!
Horizontal and Vertical Lines
Practice
Determine the slope given the following graph:
Click here to check your answer.
(C) 2017 MATH IN DEMAND