Does anyone know how to do these types of problems?

Can some one me with this math problem?

Which of the expressions (on the photo document i inserted) together represent all solutions to the following equation? 8cos(12x)+4=-4 *the answer should be in degrees.* > i would like for someone to explain the process to find the solutions for this.

Eden has a part time job. she is paid ? 7.20 an hour the week she worked 18 and a half hours how much is she paid