Http://www.google.com/url?q=http://www.sosmath.com/algebra/inequalities/ineq01/ineq01.html&sa=U&ved=0ahUKEwjXwL6qvsnRAhUIdiYKHU8sDdkQFggPMAA&sig2=wLL4VtnQtN-9CevOb4M7Qw&usg=AFQjCNGIZD-7guk9urORDLjgMCHb1LqHJg
First search up what a lunar is then look in images and you should find your answer