Using it's concept, the rate of change between point C and point D is of 2.
The average rate of change of a function is given by the change in the output divided by the change in the input. Hence, over an interval [a,b], the rate is given as follows:
[tex]r = \frac{f(b) - f(a)}{b - a}[/tex]
Considering the points of the given linear function, we have that:
Hence the rate of change between point C and point D is given by:
r = (4 - 2)/(2 - 1) = 2.
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