How do I solve this?

Question

Julie earns 12 dollars per hour at her summer job

Write a function f(x) to describe her earnings

Evaluate your function when x=5

how many hours did she work if she earned $240

Answer 1

f(x) = 12x

f(5) = 12(5) = $60

240 = f(x) = 12x

12x =240

x = 240/12 = 20 hours to earn $240