title: DbContext not found in mvc 4
body: <p>I'm creating a web application using <code>Visual Studio 2012</code> and <code>Framework 4.5</code> and I'm using <code>MVC 4</code> and I'm stuck with a problem.</p>
  
  <p>I need to use <code>DbContext</code>  but I'cant find that in my project means I added System.Data.Entity and it still gives an error </p>
  
  <blockquote>
    <p>The type or namespace name 'DbContext' could not be found (are you
    missing a using directive or an assembly reference?)</p>
  </blockquote>
  
  <p>How can I solve this...?</p>