Your friend asks you to help her babysit and will pay you 3 pennies for the first job. You agree to help if she triples your payment for each job completed. After 2 jobs, you will receive 9 pennies, and after 3 babysitting jobs, you will receive 27 pennies.

Complete and solve the equation that finds the number of pennies she will pay you after the 9th babysitting job.