Lesson 5

The mathematical purpose of this lesson is for students to recall how verbal descriptions, tables, graphs, and equations are different representations of the same relationship. They connect an equation to a graph or table of values in the context of linear relationships. They interpret a graph to answer questions about a context. They focus on the meaning of the numbers \(m\) and \(b\) in a linear equation of the form \(y=b+mx\). Then, to preview the work in the Algebra 1 lesson, they encounter a model characterized by exponential decay. This lesson parallels the work in the associated Algebra 1 lesson, except students are revisiting linear relationships here, and will encounter exponential relationships there. When students explain how a graph or expression representing a model relates to the situation it represents, they are contextualizing the representation (MP2).