Because the vast majority of new users coming to the site are here to ask a question, not to answer one. Additionally, questions are often asked by someone who has never asked a question on SO before, or has only asked a few. Answers tend to be asked by people who have already answered a lot. When people start answering they tend to keep answering and stay around for a while. When people ask a question they tend to leave when their problem is solved, either forever, or for a while. (Note that all of this is perfectly fine; none of this is improper behavior, or is doing the opposite, it's just the most common.)
Since most people answering questions have the opportunity and motivation to experiment on their own and learn based on the feedback they are given (without being driven off of the site), unlike those asking questions, it's just not as important to emphasize answering in the FAQ. By an large just look at both your answers, as well as that of other answers to questions you're familiar with, see which ones get voted up and which get voted down; this will help you determine what the community values and what it doesn't (also learn that there are occasional outliers that you need to be able to ignore).