Question

Which equation below represents the inverse function

Answer 1

When you are given a function, you usually have its expression solved for one variable, in terms of the other. In this case, you have an expression for c, written in terms of n:

$c = 20n+15$

To compute the inverse, you simply have to solve the expression for the other variable, so in this case we want an expression like

$n = \text{an expression in terms of } c$

We start by subtracting 15 to both sides:

$c-15 = 20n$

and then divide both sides by 20 to get the final result:

$n = \cfrac{c-15}{20}$