Area with Algebra: Decreasing Length (1/7) | Binomial multiplication, explained

In this lesson, Emily and Mauricio explore situations in which a new garden is formed by decreasing the length of an original garden. First, the students find the area of the new garden when the particular increase in length is given. For example, the length of a garden is decreased by 4 ft and then by 7 ft. For each given decrease, the students employ different methods to find the area of the new garden. Then they generalize their methods for an unknown decrease in length and express their generalizations using algebra.

In this video, Mauricio and Emily make sense of a new situation in which the length of a given garden is decreased by 4 feet. They make a prediction about how this decrease will affect the area of the new garden.