String Search / If Statement

If $Facebook = a letter from A-Z the link should be Welcome to Facebook - Log In, Sign Up or Learn More
If $Facebook = Just numbers it should be Log In | Facebook
If $Facebook = null Test should’t show up on the page.
I get an error on if ($facebook => 2 {?> how do i fix this?

<td colspan=“1” valign=“top”><?php if(preg_match(“/[a-z]/”,$facebook)) { ?><a target=“_blank” href=“;?=$Facebook?&gt;”<?}
if ($facebook => 2 {?><a target=“_blank” href=“;?=$Facebook?&gt;”<?php}?> />test</td>

You mean >=, rather than =>