Javier filled his gas tank with 8 gallons of unleaded gas for a cost of $15.12. How much will it cost to fill a 14-gallon tank?

How do you solve a question like this?

Sample response: if the graph passes the horizontaline test, then the function is one to one. functions that are one to one have inverses that a therefore, the inverse is a hinction compare your response to the sample response above. what did you include in your explanation? a reference to the horizontal-line test d a statement that the function is one-to-one the conclusion that the inverse is a function done

What does independent variable and dependent variable mean in math?