Lesson 15: Efficiently Solving Inequalities

Efficiently Solving Inequalities

Testing for Solutions

5 min

Problem

For each inequality, decide whether the solution is represented by $x < 2.5$ or $x > 2.5$ .

$\text-4x + 5 > \text-5$

$\text-25>\text-5(x+2.5)$

Answer

$x<2.5$
$x>2.5$

Sample Response

$x<2.5$
$x>2.5$

Responding to Student Thinking

Points to Emphasizepoints_to_emphasize

Response: If students struggle with testing points to determine the direction of the inequality in the solution, plan to revisit this concept when opportunities arise over the next several lessons. For example, make sure to invite multiple students to share their thinking about the direction of the solutions in this activity:

Standards

Addressing

7.EE.4·Use variables to represent quantities in a real-world or mathematical problem, and construct simple equations and inequalities to solve problems by reasoning about the quantities.
7.EE.B.4·Use variables to represent quantities in a real-world or mathematical problem, and construct simple equations and inequalities to solve problems by reasoning about the quantities.