# Which is the correct answer?

## The table below shows the linear function f. Determine the average rate of change of the given function over an interval [-5, -2].

Jun 22, 2018

$- 3$

#### Explanation:

$\text{the average rate of change of "f(x)" over an interval}$
$\text{between 2 points "(a,f(a))" and "(b,f(b))" is the}$
$\text{slope of the secant line joining the 2 points}$

$\frac{f \left(b\right) - f \left(a\right)}{b - a}$

$\text{here the interval "[a,b]" is } \left[- 5 , - 2\right]$

$\left(a , f \left(a\right)\right) = \left(- 5 , 19\right) \text{ and } \left(b , f \left(b\right)\right) = \left(- 2 , 10\right)$

"average rate of change "=(10-19)/(-2-(-5)

$\textcolor{w h i t e}{\times \times \times \times \times \times \times \times} = \frac{- 9}{3} = - 3$