So the question asks to combine like terms. This means it wants you to add the terms that are the same. For example, if you have 2n and 3n, and a question asks you to combine like terms, you would add them together and you would have 5n. In this equation, we see the terms n, and we see the numbers. So we need to simplify so that the equation has only one term with n, and only one term with numbers. So I will split it into two parts: (8n - n) + (13 + 5). Now you can solve this and you are left with 7n + 18. Therefore your answer is 7n + 18. Hope this helps. :D Feel free to ask questions about my explanation or ask any other questions.
