Lesson objective: Understand that nonlinear functions can be represented using tables, graphs, and written descriptions.

Students bring prior knowledge of different representations for linear functions from 8.F.A.3. This prior knowledge is extended to nonlinear functions as students create and find equivalent tables, graphs, and written descriptions for the same nonlinear function. A conceptual challenge students may encounter is understanding that a graph is not a picture, but rather it shows a relationship between two variables.

The concept is developed through work with tables and graphs, which are equivalent ways to show a relationship between two variables.

This work helps students deepen their understanding of equivalence because any of the different representations can be used to show a relationship between two variable.

Students engage in Mathematical Practice MP.2 (reason abstractly and quantitatively) as they match written descriptions of nonlinear functions to graphs and tables.

**Key vocabulary:**

- coordinate pairs
- discontinuity
- function
- linear
- nonlinear

**Special materials needed:**

- print out and cut up the card sort items that are in additional materials