Ahmed Gaafer

$('.delete_btn').click(function(){
  var key = $(this).attr("key");
  $('.client'+key).remove();
});  

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<table id="client_table">
    <tbody>
        <tr class="client1">
            <td>1</td>
            <td>Content</td>
            <td><input class="delete_btn" type="button" key="1" value="Delete"></td>
        </tr>
    </tbody>
</table>