Image not showing on custom homepage

I created a custom homepage. It’s nothing complex… The only thing in the #mainContent section is an image. The alt tag shows but not the image (I realize this is not suppose to happen). The image is located in the images folder (images/home_image.jpg). The home.css is located in the css folder (css/home.css).

Here is what is in the home.php:

<?php get_header(); ?>

<div id="mainContent">
	<img src="images/home_image.jpg" alt="XXXXXXXX" width="845" height="700" />
</div><!-- END mainContent-->

<?php get_sidebar(); ?>

<?php get_footer(); ?>

Here is what is in the home.css file:

#mainContent {
	float: right;
	width: 850px;
	min-height: 517px;
}

Unfortunately I cannot post a link to the site, as I am testing locally. Any assistance would be greatly appreciated. Cheers!