In this lesson, students formalize their descriptions from the previous lesson by writing equations where one function is defined in terms of another. Using function notation helps to keep the focus on the inputs and outputs of the function as they make sense of vertical and horizontal translations. Students compare graphs, tables, equations, and contexts of functions as they connect different representations of horizontal and vertical translations (MP7). This lesson purposefully keeps the focus on transformations that are a single vertical or horizontal translation, and in future lessons, students will build on the insights they learn here to make sense of multiple transformations at once.
Lesson overview
 2.1 Warmup: What Happened to the Equation? (5 minutes)
 2.2 Activity: Writing Equations for Vertical Translations (15 minutes)

2.3 Activity: Heating the Kitchen (15 minutes)
 Includes "Are you Ready for More?" extension problem
 Lesson Synthesis
 2.4 Cooldown: What Did You Do to My Graph? (5 minutes)
Learning goals:
 Use function notation to represent a vertical or horizontal translation from one graph to another.
Learning goals (student facing):
 Let’s represent vertical and horizontal translations using function notation.
Learning targets (student facing):
 I can use function notation to represent a vertical or horizontal translation from one graph to another.
Required materials:
 Graphing technology
 Graph paper
Required preparation:
 Provide 1 half or quarter sheet of graph paper for each student during the Lesson Synthesis.
Standards:
 This lesson builds on the standard: CCSS.HSFIF.AMS.FIFMO.A1.IF.A
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