add days to date php

<?php 
// PHP program to add days to $Date 
  
// Declare a date 
$date = "2019-05-10"; 
  
// Add days to date and display it 
echo date('Y-m-d', strtotime($date. ' + 10 days')); 
  
?> $effectiveDate = date('Y-m-d', strtotime("+3 months", strtotime($effectiveDate)));$date = new DateTime('2020-11-24');
$date->add(new DateInterval("P9D"));

echo $date->format('Y-m-d');<?php
  // adding extra days to date 
  
  // Steps:
	// 1) using carbon
    // 2) using strtotime
      
    //Step 1
  $date = date('Y M d h:i:s') // 2020 09 22 22:09:26 UTC
  
  $new_date = Carbon::parse($date->addDays(1); // adds extra day
                            
  // Step 2
  $date = date('Y M d h:i:s') // 2020 09 22 22:09:26 UTC
  
  echo $new_date = date('Y M d h:i:s', strtotime($date. '+1 day'));
?>$date = "Mar 03, 2011";
$date = strtotime($date);
$date = strtotime("+7 day", $date);
echo date('M d, Y', $date);