Question

Identify the dependent and independent variable. Write a function in function notation and use the function to solve the problem.A plumber charges $70 per hour plus $40 for the call.

Answer 1

Dependent variable = C (total charges)

Independent variable = x (number of hours he has worked)

Step-by-step explanation

We want to write a function to represent the problem and then identify the dependent and independent variable.

Let the number of hours the plumber works be x.

So, we have that the total charges will be equal to the charge for the call ($40) plus the charges per hour multiplied by the total number of hours.

That is:

C = 40 + 70 * x

C = 40 + 70x

A dependent variable is one that depends on other variables in a function for its own value.

As we can see, the charges (C) depends on the number of hours (x) that the plumber works.

So, C is the dependent variable.

The independent variable does not depend on other variables, so the independent variable is the number of hours (x).