So far in the unit, students have primarily used descriptions, expressions, and equations to represent relationships and constraints. In this lesson, they revisit the idea that graphs can be a useful way to represent relationships. Students are reminded that each point on a graph is a solution to an equation the graph represents. They analyze points on and off a graph and interpret them in context. In explaining correspondences between equations, verbal descriptions, and graphs, students hone their skill at making sense of problems (MP1).
In this lesson, students are also introduced to the use of graphing technology to graph equations. This introduction could happen independently as long as it precedes the second activity in the lesson.
Lesson overview
 5.1 Warmup: Which One Doesn't Belong: Hours and Dollars (5 minutes)
 5.2 Activity: Snacks in Bulk (10 minutes)

5.3 Activity: Graph It! (20 minutes)
 Includes "Are you Ready for More?" extension problem
 Lesson Synthesis
 5.4 Cooldown: A Spoonful of Sugar (5 minutes)
Learning goals:
 Comprehend that the graph of a linear equation in two variables represents all pairs of values that are solutions to the equation.
 Interpret points on a graph of a linear equation to answer questions about the quantities in context.
 Use graphing technology to graph linear equations and identify solutions to the equations.
Learning goals (student facing):
 Let’s graph equations in two variables.
Learning targets (student facing):
 I can use graphing technology to graph linear equations and identify solutions to the equations.
 I understand how the coordinates of the points on the graph of a linear equation are related to the equation.
 When given the graph of a linear equation, I can explain the meaning of the points on the graph in terms of the situation it represents.
Required materials:
 Graphing technology
Required preparation:
 Acquire devices that can run Desmos (recommended) or other graphing technology.
 It is ideal if each student has their own device. (If students typically access the digital version of the materials, Desmos is always available under Math Tools.)
Standards:
 This lesson builds on the standards: CCSS.8.EE.BCCSS.8.F.B.5MS.8.F.5MO.8.F.B.5MO.8.EEI.B
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