Inequalities
Overview
Inequalities describe relationships where one quantity is greater than, less than, or not equal to another. Unlike equations, which pin down a single value, an inequality defines a whole range of values that satisfy a condition. From budgeting constraints to engineering tolerances, inequalities model any situation where limits apply rather than exact targets.
This lesson covers the four inequality symbols, how to represent solution sets on a number line using open and closed circles, and how to solve linear inequalities. You will also learn to shade regions on a Cartesian graph defined by linear inequalities. Higher tier extends into quadratic inequalities and harder region problems.
Objectives
- Understand and use the inequality symbols
- Understand and use the convention for open and closed intervals on a number line
- Solve simple linear inequalities in one variable and represent the solution set on a number line
- Represent simple linear inequalities on rectangular Cartesian graphs
- Identify regions on rectangular Cartesian graphs defined by simple linear inequalities
- [Higher] Solve quadratic inequalities in one unknown and represent the solution set on a number line
- [Higher] Identify harder examples of regions defined by linear inequalities
Mind map
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Flashcards
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Inequalities. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- Solve 3x + 2 > 14. A) x > 4 B) x > 6 C) x > 3 D) x < 4 Answer: A
- Which number line correctly shows x <= 3? A) Open circle at 3, arrow right B) Filled circle at 3, arrow left C) Open circle at 3, arrow left D) Filled circle at 3, arrow right Answer: B
- Solve -2x > 6. A) x > -3 B) x < -3 C) x > 3 D) x < 3 Answer: B
- Which integers satisfy -1 < x <= 3? A) -1, 0, 1, 2, 3 B) 0, 1, 2, 3 C) 0, 1, 2 D) -1, 0, 1, 2 Answer: B
- On a graph, the region below the line y = 2x + 1 (not including the line) is described by: A) y >= 2x + 1 B) y <= 2x + 1 C) y > 2x + 1 D) y < 2x + 1 Answer: D
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Recommended Books
Practice Mock Questions
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