Algebra Lesson Plan: Solving Absolute Value Equations
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.