It seems inappropriate that your instructor is asking questions on topics that have not been covered in class or mentioned in your book. You might want to have a talk with your academic advisor about this.
Since we cannot replace the missing course material, try using the link (provided in the earlier reply) to find some lessons on complex numbers, and see if you can learn enough material to have a go at this. (Short version: View the "i" as a variable; you're wanting to find the y-value that makes the i-terms equal, and the x-value that makes the other terms equal.) But you'll mostly want to find an academic placement appropriate to the background material that you have.
Eliz.