annual payments

On December​ ;31, Beth Klemkosky bought a yacht for ​$50,000. She paid ​$12,000 down and agreed to pay the balance in 12 equal annual installments that include both the principal and 13 percent interest on the declining balance. How big will the annual payments​ ;be?

a.  On December​ ;31, Beth Klemkosky bought a yacht for ​$50,000 and paid ​$12,000 ​down, how much does she need to borrow to purchase the​ ;yacht?