I didn't understand Yahoo Answers at all. I found writing a few good and quality answers, but the total number of visitors was about 60-70... for a few 250-300 words answers... Maybe not so powerful anymore or ... not sure!
Yahoo Answer is a good place where u can ask and give Q answers, and also can give no-follow links when u get 250 points.
Hello, It is a very good method when the Yahoo answers when you're on the SEO course you are trying to answer that question, you must be able to verify the site you will be able to answer better than and help to drive traffic for your site if your answer is relevant and good.
You can post your link on Yahoo Answers, it is a good backlink but if you spam your link your account will be removed.