Question

a line of best fit is $f(x)approx - 0.86x + 13.5$ for the set of points in the table. using the equation for the line of best fit, what is a good approximation for the value of the function, $f(x)$, when $x = 18$?

$x$	$f(x)$
3	10
5	10
6	8
7	9
8	5
0	6

3
-2
12
-5

Explanation:

Step1: Substitute x value

$f(18)\approx - 0.86\times18 + 13.5$

Step2: Calculate result

$f(18)\approx-15.48 + 13.5=-1.98\approx - 2$

Answer:

-2