I need to display this in a max banner box but the banner not show

<div class="banner" style="position:relative;float:left"><a href="http://www.mydomain.com/random-ads-300x250.php" target="_blank"> fgd</a></div>
<div class="banner" style="position:relative;float:right;"><a href="http://www.mydomain.com/random-fun-ads-300x250.php" target="_blank">ghfgh</a></div>

i have the banners rotating on these urls. But i can not display them