Prior Knowledge: Students should have learned how to write equations, translate sentences into equations and equations into sentences, solve one-step equations using addition and subtraction, solve simple equations using multiplication or division, solve multi-step equations and solve equations with variables on both sides of the equation. Finally students will learn how to solve equations involving absolute value.

Common Core State Standards

A.REI.1: Explain each step in solving a simple equation as following from the equality of numbers asserted at the previous step, starting from the assumption that the original equation has a solution. Construct a viable argument to justify a solution method.

A.REI.3: Solve linear equations and inequalities in one variable, including equations with coefficients represented by letters.

Mathematical Practice(s):

**3** Construct viable arguments and critique the reasoning of others.

**7** Look for and make use of structure.

Learning Target(s)

- I can apply order of operations and inverse operations to solve equations
- I can construct an argument to justify my solution process

Essential Question(s)

1.What is the difference in solving a regular equation and an equation with variables on both sides?

2. Do you treat absolute value equations any differently than regular equations?

Vocabulary: inverse operation, isolate, variable, constant, reciprocal, coefficient, absolute value bars, absolute value

## LESSON

Notes:

- Instruct that minus and negative are equivalent
**GOAL**: to isolate the specified variable- Instruct that what is done on one side of the equation (= sign), must be done on the other side of the = sign.

Watch the video on absolute value equations on Khan Academy.

- Go to www.khanacademy.org
- Scroll down and click on Algebra (2
^{nd}tab under Math) - At the top, type in the search bar: absolute value equations
- This will bring you to the video lesson. The length is 10:41.
- After watching the video, click on the green button above the video that says: Practice this concept
- This will give you 8 problems to solve. There is a hint button for the students if they need it. If they students need more practice problems, Khan Academy will give them more of the same type of problems.

** Reminder for students: that –x is the same as -1x & x is the same as 1x.*

Guided Practice: Khan Academy offers practice problems. Do this together as a class.

Independent Practice: Approximately 5-15 problems to be done alone. These problems can be pulled from any textbook or other resource.

Closure/Review: Quick class discussion on what was learned today. You can ask leading questions but let the students come up with what they learned today.

Exit Ticket: This is to be done the last 3-5 minutes of class and given to you (by hand or in a designated area of your room) as they leave class. Possible question(s):

Give them one more problem from Khan Academy for them to solve on paper.

## This post is part of the series: Beginner Algebra

- Lesson Plan: Solving One-Step Equations using Addition or Subtraction
- Lesson Plan: Solving One-Step Equations using Multiplication or Division
- High School Math Lesson Plan: Solving Multi-Step Equations
- Lesson Plan: Solving Equations with Variables on Both Sides of the Equation
- Algebra Lesson Plan: Solving Absolute Value Equations