<em>It is hard to explain but for step one you need to take the dotted line and the shape above hat and move it underneath the other shape to make a perfect rectangle.</em>
<em>Step two since the dotted line is our new bottom. It has a length of 7. In this step we multiply 3 times 7 </em>
<em>Step 3 this is the final step in which 3 times 7 equals 21.</em>
