# Lesson 20

Interpreting Inequalities

These materials, when encountered before Algebra 1, Unit 2, Lesson 20 support success in that lesson.

### Lesson Narrative

The mathematical purpose of this lesson is to support students in making sense of language used to describe situations that can be modeled with inequalities. It also gives students an opportunity to interpret solutions of inequalities in terms of the situations they describe. Students practice representing solutions to inequalities using multiple representations (verbally, on the number line, and symbolically). This builds on the work students did in grade 7, when they represented situations and solved problems using inequalities.

This work prepares students for the associated Algebra 1 lesson when they interpret and solve more complex inequalities in terms of the situations. Students look for and make use of structures (MP7) as they recognize the connection between inequalities, situations, and graphs of inequalities

### Learning Goals

Teacher Facing

• Interpret the results of inequalities in terms of a situation with emphasis on hidden constraints.
• Model situations using multiple representations of inequalities.

### Student Facing

• Let’s interpret the meaning of situations with phrases like “at least,” “at most,” and “up to.”

### Required Preparation

Print and cut up slips from the blackline master. Prepare 1 copy for every 2 students.