School Improvement in Maryland

Lesson Plan: Lesson plans were written by Maryland mathematics educators and could be used when teaching the concepts.

Goal 1 Functions and Algebra

Expectation 1.2 The student will model and interpret real-world situations using the language of mathematics and appropriate technology.

Indicator 1.2.2 The student will solve linear inequalities and describe the solutions using numbers, symbols, and/or graphs.

Lesson Content

Linear Inequalities


  • Students will use technology to graph and evaluate linear inequalities.
  • Students will write and manipulate inequalities for use on a graphing calculator.
  • Students will use knowledge of intercepts to analyze inequalities.

Materials Needed

Calculator Skills

  • Entering and evaluating inequalities on a graphing calculator.
  • Using the trace and intercept capabilities of the calculator.


Class discussion

Lesson Structure

Concept Development for this lesson uses the following worksheet: Lilies and Daisies.
Teacher tips for using Lilies and Daisies

    Evaluating Inequalities Using the Calculator

    Have students work in pairs to write an inequality for the given situation and solve the inequality in slope-intercept form.


    Students will enter the inequality into the calculator to get an appropriate picture of the situation. Students will answer questions using the calculator and mathematical reasoning about the inequality.

    Class Discussion

    Students will explain the mathematical knowledge used to answer various questions throughout the lesson.

    Additional Practice

    These problems are provided for you to use in any one of a variety of ways such as homework, an individual check for understanding, review, or quiz. They are provided at the end of the lesson.