Movies: Dec. 1, 2009 – Simon’s Subtraction

In this video Simon demonstrates how to solve a difficult borrowing subtraction problem by using symbolic blocks and expanded form. We are using these methods on our way to the standard algorithm. These steps are important to us so that we know why the standard algorithm works. Why do we use the standard algorithm at the end of the day? Well, the goal is to solve these problems in the quickest, most accurate way. These methods help us get there with sound fundamentals.