In this lesson, students continue to develop their understanding of inverse functions. Previously, students wrote inverses for functions where the input and output were related by one operation. Here, they write inverses for functions that are defined using multiple operations, recognizing that the process is comparable to their earlier work of solving for a variable. Students also interpret the inverse functions in terms of situations, and in doing so practice reasoning quantitatively and abstractly (MP2).
The functions students see here and in the next lesson are limited to linear functions.
Lesson overview
 16.1 Warmup: Shopping for Cookbooks (5 minutes)

16.2 Activity: From Celsius to Fahrenheit (10 minutes)
 Includes "Are you Ready for More?" extension problem
 16.3 Activity: Info Gap: Custom Mugs (20 minutes)
 16.4 Optional Activity: Tables and Seats (15 minutes)
 Lesson Synthesis
 16.5 Cooldown: Carnival Functions (5 minutes)
Learning goals:
 Find the inverse of a linear function by solving an equation for the input variable.
 Interpret an inverse function in terms of the quantities in a situation.
Learning goals (student facing):
 Let’s find the inverse of linear functions.
Learning targets (student facing):
 I can explain the meaning of an inverse function in terms of a situation.
 When I have an equation that defines a linear function, I know how to find its inverse.
Required materials:
 Preprinted slips, cut from copies of the blackline master
Standards:
 This lesson builds on the standards: CCSS.HSACED.A.2MS.ACED.2CCSS.HSACED.A.4MS.ACED.4MO.A1.CED.A.2MO.A1.CED.A.4
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