custom field displaying even if there is no value

I have a custom page template with custom fields and I can’t figure out how to make it so if the field is empty it doesn’t display. I’ve looked at info regarding empty ()

and they show this as an example

<?php
$var = 0;

// Evaluates to true because $var is empty
if (empty($var)) {
    echo '$var is either 0, empty, or not set at all';
}

// Evaluates as true because $var is set
if (isset($var)) {
    echo '$var is set even though it is empty';
}
?>

but I’m not sure how to incorporate it with my code here

<a href="<?php echo get_post_meta($post->ID, "google", $single = true); ?>"><img src="<?php echo bloginfo('template_url'); ?>/images/google.png" />

here is the page it is displayed on

https://firsttuesdayusa.com/profiles/…rs/marcy-cole/