Unit 4
Keeping the Equation Balanced
Linear Equations and Linear Systems
Lesson 2
8.EE.C: Analyze and solve linear equations and pairs of simultaneous linear equations
Expressions and Equations
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What's the Relationship?
Unit 4 ● Lesson 2
1 min individual - 1 min team share - 3 mins class share
Page 12
Why is the left hanger balanced while the right hanger is unbalanced.
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Slides are CC BY NC Kendall Hunt Publishing. Curriculum excerpts are CC BY Open Up Resources, with adaptations CC BY Illustrative Mathematics.
Let's figure out unknown weights on balanced hangers.
Unit 4 ● Lesson 2
We will be able to add or remove blocks from a hanger and keep the hanger balanced so that we can understand how balanced hangers represent equations.
Learning
Goal
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Where were we? Where are we? Where are we going?
Unit 4 ● Lesson 2
Agenda Review
You are successful today when...,
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Slides are CC BY NC Kendall Hunt Publishing. Curriculum excerpts are CC BY Open Up Resources, with adaptations CC BY Illustrative Mathematics.
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Slides are CC BY NC Kendall Hunt Publishing. Curriculum excerpts are CC BY Open Up Resources, with adaptations CC BY Illustrative Mathematics.
2.2 Activity: Hanging Blocks
I can represent balanced hangers with equations
10 mins total
4 mins Individual - 1 mins Group - 5 mins Class Share
The hanger will tip to the left since only 2 triangles were taken off the left while 3 triangles were taken off the right, which means more weight was taken off the right side making it lighter than the left side.
A square weighs 1.5 (3/2) grams. 3 triangles = 2 squares. The hanger can be represented by the equation
3s + 2(1) = s + 5(1). 2s = 3
s = 3/2
pg 13
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Slides are CC BY NC Kendall Hunt Publishing. Curriculum excerpts are CC BY Open Up Resources, with adaptations CC BY Illustrative Mathematics.
2.2 Activity: Hanging Blocks
I can represent balanced hangers with equations
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Slides are CC BY NC Kendall Hunt Publishing. Curriculum excerpts are CC BY Open Up Resources, with adaptations CC BY Illustrative Mathematics.
2.3 Activity: More Hanging Blocks
I can represent balanced hangers with equations
15 mins total
2 mins Individual - 5 mins Group - 8 mins Class Share
A: 3 + 3(6) + s = 5s +6
3 + 18 + s = 5s + 6
21 + s = 5s + 6
15 = 4s
B: 2(6) +2p = 2p +3 +3 +6
12 + 2p = 2p + 12
0 = 0
pg 13
Infinite Solutions
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Slides are CC BY NC Kendall Hunt Publishing. Curriculum excerpts are CC BY Open Up Resources, with adaptations CC BY Illustrative Mathematics.
Keeping the Equation Balanced
I can represent balanced hangers with equations
An equation is a statement that two expressions have the same value. The equal sign tells you that the expressions on either side must have the same value
Both representations have sides that are equal in value, even if the actual value of a side is unknown. Changing the value of one side of a hanger or equations means changing the value of the other side by the same amount.
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Lesson Synthesis
Slides are CC BY NC Kendall Hunt Publishing. Curriculum excerpts are CC BY Open Up Resources, with adaptations CC BY Illustrative Mathematics.
Changing Blocks
I can represent balanced hangers with equations
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Cool-down
Slides are CC BY NC Kendall Hunt Publishing. Curriculum excerpts are CC BY Open Up Resources, with adaptations CC BY Illustrative Mathematics.
Unit 4 ● Lesson 2
Learning
Targets
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Unit 2 ● Lesson 1
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Slides are CC BY NC Kendall Hunt Publishing. Curriculum excerpts are CC BY Open Up Resources, with adaptations CC BY Illustrative Mathematics.
This slide deck is copyright 2020 by Kendall Hunt Publishing, https://im.kendallhunt.com/, and is licensed under the Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0), https://creativecommons.org/licenses/by-nc/4.0/.
All curriculum excerpts are under the following licenses:
IM 6–8 Math was originally developed by Open Up Resources and authored by Illustrative Mathematics, and is copyright 2017-2019 by Open Up Resources. It is licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0). OUR's 6–8 Math Curriculum is available at https://openupresources.org/math-curriculum/.
Adaptations and updates to IM 6–8 Math are copyright 2019 by Illustrative Mathematics, and are licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0).
Adaptations to add additional English language learner supports are copyright 2019 by Open Up Resources, and are licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0).
The Illustrative Mathematics name and logo are not subject to the Creative Commons license and may not be used without the prior and express written consent of Illustrative Mathematics.
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