Question

a line of best fit is f(x) = -0.86x + 13.8 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? -5 -2 3 12

Explanation:

Step1: Substitute \(x = 18\) into the equation

Given \(f(x)=- 0.86x + 13.8\), substitute \(x = 18\):
\(f(18)=-0.86\times18 + 13.8\)

Step2: Calculate the product

\(-0.86\times18=-15.48\)

Step3: Calculate the sum

\(f(18)=-15.48 + 13.8=-1.68\approx - 2\)

Answer:

\(-2\) (corresponding to the second option)