title: Find all ids from list in another list
body: <p>I have a list containing models where each model has a number.</p>
  
  <p>Now I'd like to search another list containg other models where each model could potentially have the number from the first list.</p>
  
  <p>This is how my models look:</p>
  
  <pre><code>public class Task 
  {
     int AddressId; //foreign key
  }
  
  public class Address
  {
     int Id; //primary key
  }
  </code></pre>
  
  <p>Now I have a list of addresses and a list of tasks.
  I'd like to filter my list of tasks to only those tasks where the AddressId is inside my addresses list.</p>
  
  <p>How would my linq look like?</p>
  
  <pre><code>result = tasks.Where(t =&gt; t.AddressId == ???)
  </code></pre>