WikiAnswers can be considered reliable to a certain extent, but other sources should always be used to confirm the reliability of the answer. Anyone on WikiAnswers can answer a question, but the given answers can be selected by other users as helpful or not helpful.
WikiAnswers is a site in which people can ask questions about anything and other people answer those questions. From there, people can select if the answer was helpful, somewhat helpful or not helpful. This voting system makes most of the answers on the site mostly reliable, but many new questions initially have incorrect answers given by people who just enter random information that doesn't relate to the question and aren't voted on yet; because of this, it is better to look at older questions in WikiAnswers that have had people vote on if they are correct or incorrect.