Add Google Map Dynamicly

I have a custom page template where $_POST['lat'], $_POST['lon'], and $_POST['address'] . How do I add a map at the bottom of the page with this information?

All the content on the page is written in PHP (that is, if you went to this page in the editor, there would appear to be no content on the page). You can see the page at https://pmai.us/directory/?id=2589. The map show go right below the blue bar near the bottom, where there is a missing image symbol.

Thanks for your help!
~Larry