WeBWorK Standalone Renderer

Given the numerical values shown for the function $f(x)$ , find approximate values for the derivative of $f(x)$ at each of the $x$ -values given.

$x =$	0	1	2	3	4	5	6	7	8
$f(x) =$	-18	-20	-21	-22	-25	-25	-23	-21	-19
$f'(x) =$

What seems to be the greatest rate of change of $f(x)$ ?
rate of change =

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