The common difference

To find the common difference, you need to work out how much the terms are increasing or decreasing by from one term to the next.

For example, find the common difference and the next two terms of the following sequence.

Linear sequence diagram

We can see that these terms go up by {3} every time, or we state that the common difference is {3}. The next two terms will then be {16} and {19}.

Linear sequence diagram
Question

Find the common difference and the next two terms of the following sequence.

Linear sequence diagram

The common difference is {-2}. The next two terms are {8} and {6}.

Linear sequence diagram