$(document).ready(function() {
  	$('a.activator').click(function() {
		var $nextDiv = $(this).siblings('div');
		var $closedimg = $(this).children().children('img.closedimg');
		var $openedimg = $(this).children().children('img.openedimg');

		if ($nextDiv.is(':visible')) {
			$openedimg.hide();
			$closedimg.show();
		} else {
			$openedimg.show();
			$closedimg.hide();
		}

		$nextDiv.slideToggle('500');
  });
});