JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>
<form id="form3" method="post" action="">
<h3>
Form 3
</h3>
<input type="checkbox" id="terms"> Terms
</form>

<form id="form1" method="post">
  <h3>
  Form 1
  </h3>
  <input type="checkbox" id="cash" value="cash"/> Cash
  <input type="submit" value="submit" />
</form>

<form id="form2" method="post">
  <h3>
  Form 2
  </h3>
  <input type="checkbox" id="visa" value="visa"> Visa
  <input type="submit" value="submit" />
</form>

JavaScript

$(function(){
  $("#form1, #form2").on('submit', function(){
    if($("#terms:checked").length) {
      $(this).submit();
    }
    else {
      alert('Please accept the terms');
    }
    return false;
  })
})