#### Answer

One method is add zero lines and the other method is to add zeros on the next partial product. Take a look at work step by step to see how to prove it.

#### Work Step by Step

-----------
-Using zero lines
___291
__*307
----------
__2037
__000
+873
----------
_89,337
-Adding zeros
___291
__*307
----------
__2037
+8730
---------
_89,337