Event List filtered by distance to the event

I got the following code:

 global $wpdb;     
 $user = wp_get_current_user();
	$user_id = $user->ID;
 
	$koordinaten = $wpdb->get_results("SELECT location_latitude,location_longitude FROM nogfd_em_locations WHERE location_owner = ".$user_id); 
  foreach($koordinaten as $koordinate)
  {
    $koordinate1 = $koordinate->location_latitude;
	$koordinate2 = $koordinate->location_longitude;
  }
	
	echo EM_Events::output( array('limit'=>'10','near'=>'$koordinate1,$koordinate2','near_unit'=>'km','near_distance'=>'1') );

My idea is that every user just creates one location that is his house. Therefore I can filter the coordinates of his location in the database. As I am not experienced with php and WordPress overall (doing this for a few days) I do not know how i can get this to work. The problem is that ‘near’=>'[…]’, only accepts numbers and no variables. Any help is appreciated (probably the most newbie question and I just need to convert the variable to a string or something:))