title: Time Subtract in PHP
body: <p>I need help to subtract 2 times in PHP.</p>
  
  <p>Example:</p>
  
  <pre><code>$date1 = 02:40;
  $date2 = 00:00;
  
  $finaldate = $date1 - $date2;
  </code></pre>
  
  <p>the correct answer will be 21:20.</p>