Answer
$A(x) =5 x-10$ and $A^{\prime}(x)=5=f(x)$
Work Step by Step
The function starts from 2 to $x$ on the x-axis, and intercepts with the y-axis at $y$ = 5, so the function will be
$$A(x) = yx =5(x-2)=5 x-10$$
Differentiate this function to get
$$A^{\prime}(x)=5=f(x)$$