Answer
$g(x)=y=5x-2$
Work Step by Step
We need to find the line equation by using the two points: $(1,3); (2,8)$
$\dfrac{y-3}{8-3}=\dfrac{x-1}{2-1}$
This gives: $y-3= 5(x-1)$
Thus, we have the linear equation for the function $f(x)$:
$g(x)=y=5x-2$
