District 11 Division of Operations & Instruction
Mathematics






Integrated Algebra & Geometry, Unit 2: Linear Functions (@ 18 days)

Overview 
The overarching theme of the unit is usefulness of mathematics in the real world. In this unit you will use linear equations to graph and model real-life situations. You will learn to write and graph linear equations given the starting value/y-intercept and the rate / slope of the line. Using the properties of linear functions, you will apply these properties to real - world problems. You will be able to distinguish between linear and non-linear functions as well as identify a direct variation as a specific case of a linear function. You will learn the effects of changes in the slopes and y-intercepts of linear functions. Each lesson is introduced by an essential question that serves as the foundation for the teaching objective of a particular lesson.

 

For Teachers
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 Quarter Overview

Daily Lessons Intro 1 2 3 4 5 6 7 8

Enduring Understandings are important ideas that students should carry with them years beyond the instruction received this year.

  • Algebra is a language.

  • Numbers can be represented, ordered, and communicated in many different forms.

  • Solutions must be reasonable.

  • Computation is a vital mathematical tool.

  • Computation and reasoning are a vital mathematical tools.

Essential Questions are the most important “big picture” questions students should be able to answer after completing learning activities.

  • How do you demonstrate equivalent numbers using various forms?

  • Why do we need to represent, order, and communicate numbers?

  • How do you select and apply computational methods to solve a problem?

  • How do you justify your solution as reasonable?

Standards: Highest Frequency High Frequency Other Standards and E-Skills

Standard 2: (Algebra and Functions) Students use algebraic methods to explore, model and describe patterns and functions involving numbers, shapes, data, and graphs in problem-solving situations and communicate the reasoning used in solving these problems.
2.1 Recognize, extend and use geometric, numeric, linear, or visual patterns to solve a problem.  Using the rule for a pattern to represent it in a table, graph, and problem solve.  Recognize an equation that models a given situation.
2.5a Solve simple equations
2.5b Translate English expressions and algebraic expressions
2.2 Recognizing, describing, and extending a pattern and function using tables and graphs in a problem solving situation.  Using a table to find a constant/unit rate.
2.5 Substituting in a formula to compute a value. Solving a simple linear equation in a problem solving situation. Using a linear function given in a context to solve a problem.

Standard 6: (Computation) Students link concepts and procedures as they develop and use computational techniques, including estimation, mental arithmetic, paper-and-pencil, calculators, and computers, in problem-solving situations and communicate the reasoning involve
Compute with whole numbers.
Add and subtract decimals in problem solving situations
Apply appropriate computational methods to solve a problem.
Apply computational skills to find reasonable answers

Lessons

Introduction:  Introduction to Linear Functions

Duration: @ 1-2  class periods
Standard information 2:
2.1 Recognize, extend and use geometric, numeric, linear, or visual patterns to solve a problem. Using the rule for a pattern to represent it in a table, graph, and problem solve. Recognize an equation that models a given situation.
Enduring Understanding:
Algebra is a language.
Essential Questions: What real-world situations can be modeled by linear functions? Why would we need a linear function to model a real-world situation?

Activities

  1. Introduction - This lesson represents a transition between the current and previous units. You already know the definition of a function as well as they distinguish real-world situations that represent functions. In this lesson, you will learn what makes functions become linear. You already know how to distinguish from a graph if it represents a linear or non-linear function.  Now, you will learn how to recognize real-world situations that can be modeled by linear functions. We introduce these by pointing at the pattern of repeated addition/subtraction from a starting value. You will learn to use a “shortcut” for repeated subtraction, which ends with writing an equation that models Adam’s account balance after x days. The key question that points out the usefulness of using patterns (that represent linear relationships) is question #20. The following question might lead to an interesting discussion. Then, we can summarize properties of linear patterns/functions.

  2. Practice - Student Worksheet: My Introductory Lesson

Differentiation
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Lesson 1:  Using Linear Functions

Duration: @ 1-2  class periods
Standard information 2:
2.1 Recognize, extend and use geometric, numeric, linear, or visual patterns to solve a problem. Using the rule for a pattern to represent it in a table, graph, and problem solve. Recognize an equation that models a given situation.
Enduring Understanding:
Algebra is a language.

Essential Questions:
How can we use linear functions to solve real-world problems? How does the starting value affect the graph?

Activities

  1. Introduction - In the previous unit you have learned how to determine whether the set of data is a function or not as well as properties that functions can possess. You know that a function describes the way two quantities are related.  You will use the knowledge in this unit to solve real-world situations related to linear functions. For example: On Memorial day Hayden bought a new computer at Best Buy. The computer was not on sale, it cost $672, but Hayden was offered an 18-month interest- free financing. After considering the deal, Hayden decided to buy it. He determined that he would pay off the computer within the free-interest period. How high should Hayden’s monthly payments be in order to pay off the credit card balance in 18 months? In 12 months? How would the answer change if his previous balance on the credit card was $134?

  2. Practice - Student Worksheet: Student Worksheet Lesson 1 (Writing linear equations, completing tables, graphing, and interpreting intercepts.)

Differentiation
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Lesson 2: Elements of Linear Functions

Duration: @ 1 class period
Standard information
2.1 Recognize, extend and use geometric, numeric, linear, or visual patterns to solve a problem. Using the rule for a pattern to represent it in a table, graph, and problem solve. Recognize an equation that models a given situation.
Enduring Understanding:
 
Algebra is a language.
Essential Questions:
What are two important elements that define a linear function?

Activities

  1. Introduction Lesson 2
  2. Practice Student Worksheet 2 Writing linear equations, completing tables, graphing, and interpreting intercepts, interpreting effects of changing rates and starting values on graphs.)

Differentiation
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Lesson 3:  Finding Rates From Tables

Duration: @ 1 class period
Standard information
2.1 Recognize, extend and use geometric, numeric, linear, or visual patterns to solve a problem. Using the rule for a pattern to represent it in a table, graph, and problem solve. Recognize an equation that models a given situation.
Enduring Understanding:
 
Algebra is a language.
Essential Questions:
Do you need to know the starting value in order to find the rate? What must you know in order to find the rate?

Activities

  1. Introduction  Lesson 3

  2. Practice - Student Worksheet 3 (Finding rates from tables, finding unit rates.)

  3. Test Yourself -

Differentiation
Extension:
Watch the Car Speed video (3:13) and the Bungee Jumper video (1:43) to see how time distance graphs are used to display and analyze speed.
Support:
 

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Lesson 4: Using Rates

Duration: @ 2 class period
Standard information
2.1 Recognize, extend and use geometric, numeric, linear, or visual patterns to solve a problem. Using the rule for a pattern to represent it in a table, graph, and problem solve. Recognize an equation that models a given situation.
Enduring Understanding:
 
Algebra is a language.
Essential Question:
 
How can we use rates to make decisions?

Activities

  1. Introduction - Lesson 4
  2. Practice - Student Worksheet 4. 1 (Writing and interpreting equations, finding real-world meanings of rates.)
    Student Worksheet 4.2  (Comparing rates, making decisions based on better rates.)

Differentiation
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Lesson 5:  Graphs

Duration: @ 2 class periods
Standard information
2.1 Recognize, extend and use geometric, numeric, linear, or visual patterns to solve a problem. Using the rule for a pattern to represent it in a table, graph, and problem solve. Recognize an equation that models a given situation.
Enduring Understanding:
 
Algebra is a language.
Essential Question:
 
How do we find rates from graphs?

Activities

  1. Introduction -  Lesson 5  

  2. Practice - Student Worksheet 5 (Reading and interpreting graphs, finding rates from graphs, converting between units.)

Differentiation
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Lesson 6: Using Points to Find Slope

Duration: @ 3 class periods
Standard information
2.1 Recognize, extend and use geometric, numeric, linear, or visual patterns to solve a problem. Using the rule for a pattern to represent it in a table, graph, and problem solve. Recognize an equation that models a given situation.
Enduring Understanding:
 
Algebra is a language.
Essential Question:
 
How can points be used to find the slope?
Assessment:
Formative Assessment #1

Activities

  1. Introduction -  Lesson 6

  2. Practice - Student Worksheet 6.1 (Writing equations from graphs.) 
    Student Worksheet 6.2 (Graphing equations.)
    Student Worksheet 6.3 (Finding rates/slopes from tables, graphs, equations, slope formula.)

  3. Test Yourself - Formative Assessment #1

Differentiation
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Lesson 7: Direct Variations

Duration: @ 2 class periods
Standard information
2.1 Recognize, extend and use geometric, numeric, linear, or visual patterns to solve a problem. Using the rule for a pattern to represent it in a table, graph, and problem solve. Recognize an equation that models a given situation.
Enduring Understanding:
Algebra is a language.
Essential Questions:
 
Knowing how the y-intercept (starting value) affects the graph of a linear function, what will all graphs whose y-intercept is 0 have in common? How can you tell from the context of a problem if it’s a direct variation?

Activities

  1. Introduction -  Lesson 7 

  2. Practice - Student Worksheet 7.1 (Writing direct variation equations, relationship between direct variations and linear functions.)
    Student Worksheet 7.2 (More practice on direct variations, tables, graphs, interpreting tables.) 

Differentiation
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Lesson 8: Linear Equations

Duration: @ 3-4 class periods
Standard information
2.1 Recognize, extend and use geometric, numeric, linear, or visual patterns to solve a problem. Using the rule for a pattern to represent it in a table, graph, and problem solve. Recognize an equation that models a given situation.
Enduring Understanding:
 
Algebra is a language.
Essential Questions:
 
What is a reasonable mathematical model, in symbolic form, for relationships that have an initial value and a constant rate of change? How can we efficiently solve real-life problems using linear equations?

Activities

  1. Introduction - Lesson 8  

  2. Practice - Student Worksheet 8.1 (Evaluating and solving linear equations, interpreting linear equations.) Student Worksheet 8.2 (Additional practice on solving real-life problems that can be modeled by linear functions.)
    Student Worksheet 8.3 (Solving linear equations without a context.)
    Student Worksheet 8.4 (A huge variety of problems on solving linear equations. The problems were provided by Wasson High School.)

  3. Test Yourself - Formative Assessment #3

Differentiation
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