Lesson Plan: Solving Inequalities
Grade: 9th
Subject: Mathematics
Topic: Solving Inequalities
Duration: 60 minutes
Objectives: 1. Understand the concept of inequalities and their representation on a number line. 2. Solve and graph one-step and two-step inequalities. 3. Apply the knowledge of solving inequalities to real-life scenarios.
Materials: - Whiteboard or blackboard - Markers or chalk - Worksheets (links provided below) - Video resources (links provided below) - Number line posters - Graphing calculators (optional)
Introduction (5 minutes): 1. Begin the lesson by asking students if they are familiar with the concept of equations and how they are solved. 2. Explain that inequalities are similar to equations but involve comparing two expressions using symbols such as <, >, ≤, or ≥. 3. Show examples of inequalities on the board and discuss their meaning (e.g., 2x + 3 < 10 means “twice a number plus three is less than ten”). 4. Introduce the concept of representing inequalities on a number line and explain how it helps visualize the solutions.
Lesson Outline: 1. One-Step Inequalities (15 minutes): a. Review the steps for solving one-step equations. b. Explain that solving one-step inequalities follows similar steps, but with one key difference: when multiplying or dividing by a negative number, the inequality sign must be flipped. c. Provide examples of one-step inequalities and guide students through the solving process. d. Use the number line to graph the solutions and discuss the concept of open and closed circles.
-
Two-Step Inequalities (15 minutes): a. Review the steps for solving two-step equations. b. Explain that solving two-step inequalities also follows similar steps, but with the same rule of flipping the inequality sign when multiplying or dividing by a negative number. c. Provide examples of two-step inequalities and guide students through the solving process. d. Use the number line to graph the solutions and discuss the concept of shading the appropriate region.
-
Real-Life Applications (15 minutes): a. Engage students by presenting real-life scenarios that involve inequalities (e.g., “You must earn at least $10 per hour to afford a movie ticket. How many hours do you need to work to afford a $50 ticket?”). b. Discuss how to translate the scenario into an inequality and solve it. c. Encourage students to come up with their own scenarios and inequalities to solve.
Questioning and Discussion: - Throughout the lesson, ask questions to check for understanding and promote critical thinking: - What is the difference between an equation and an inequality? - Why is it important to flip the inequality sign when multiplying or dividing by a negative number? - How does graphing on a number line help us understand the solutions to inequalities? - Can you think of any real-life situations where inequalities are used?
Assessment: - Distribute worksheets to assess students’ understanding of solving inequalities. - Monitor students’ progress during class discussions and activities. - Provide feedback and clarification as needed.
Differentiation: - For students who need additional support, provide extra examples and guided practice. - For advanced students, introduce multi-step inequalities or more complex real-life scenarios. - Use graphing calculators to reinforce the concept of graphing inequalities.
Plenary (5 minutes): - Summarize the key points covered in the lesson. - Ask students to share one thing they learned or found interesting about solving inequalities. - Address any remaining questions or concerns.
Video Resources: 1. Khan Academy: Solving Inequalities (One-Step): https://www.khanacademy.org/math/algebra-home/alg-basic-eq-ineq/alg-one-step-inequalities/v/solving-and-graphing-one-step-inequalities 2. Math Antics: Solving Inequalities (Two-Step): https://www.youtube.com/watch?v=3X2sv0LpM9s
Worksheet Resources: 1. One-Step Inequalities Worksheet: https://www.mathworksheets4kids.com/inequalities/one-step/ones-1.pdf 2. Two-Step Inequalities Worksheet: https://www.mathworksheets4kids.com/inequalities/two-step/twos-1.pdf