ureech,
<!DOCTYPE html>
<html>
<head>
<title>Untitled</title>
<meta charset="utf-8">
<style type="text/css">.ajax{display:none}</style>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>
<script>
$(function() {
var inp = $("input[name='self_del[]']")
inp.on('click',function(){
$('.ajax_del').toggle(inp.is(":checked"))
})
});
</script>
</head>
<body>
<a class="ajax ajax_del" href="javascript:;">Delete</a>
<input type="checkbox" name="self_del[]" id="0" value="0">
<input type="checkbox" name="self_del[]" id="1" value="0">
<input type="checkbox" name="self_del[]" id="2" value="0">
</body>
</html>