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Inequalities

Chapter Synopsis

 

The coordinate plane is a two-dimensional surface on which we can plot points, lines and curves. It has two scales, called the x-axis and y-axis, at right angles to each other that meet at the point of origin (0, 0). In this module, students use the concept of Formula M racing to understand the concept of inequalities. What does it mean if a solid line is found on the plane and all areas below the line are shaded? This could mean that anything on the line is a tie in the race and anything in the shaded area would be a loss. In other words, we’re looking at real-life activities to teach this abstract concept.

Lesson one has students using rates to calculate the lowest rate needed to beat a world record. This lesson focuses on using the slope-intercept form of an equation to help students solve an inequality by creating a table and coordinate graph to represent the situation.

In the second lesson, students first work with different inequality symbols. They then use rates to write linear equations to calculate all possible solutions for different situations. This lesson focuses on using the slope-intercept form of an equation to help students solve an inequality with inverse operations and represent all solutions on a coordinate graph.

Formative and summative assessments are available, plus a resource sheet on inequalities and a vocabulary list.

 

Standards Addressed

Grade 8, Mathematics — Patterns, Functions and Algebra

08-10 Benchmark
F. Solve and graph linear equations and inequalities.

Y2003.CMA.S04.G08-10.BF.L08.107 / Use Algebraic Representations

07. Use symbolic algebra (equations and inequalities), graphs and tables to represent situations and solve problems.

 
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