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Recommended for: Grades 3-6

Resource: Solving an Equation for a Missing Value

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Media Type:
QuickTime Video

Length: 1m 33s
Size: 4.5 MB

In this video segment from Cyberchase, the CyberSquad must figure out the correct number code to unlock a machine. They have two numbers on one side, but are missing one of the numbers on the other side. The sum of the numbers must be equal on each side, so by subtracting the same number from each side they are able to determine the missing number.

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Transcript (Rich Text Format Document)

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Teachers' Domain, Solving an Equation for a Missing Value, published August 25, 2008, retrieved on ,
http://www.teachersdomain.org/resource/vtl07.math.algebra.equ.solvingequ/

Frame and Focus
Follow Up
Connections
Standards

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Here are some Frame, Focus and Follow-up suggestions for using this video in a math lesson.

What is Frame, Focus and Follow-up?

Frame: Let’s say you are trying to get a simple scale to balance. On one side of the scale you have a three-pound weight and a one-pound weight. On the other side, you have a two-pound weight. What would you do to make the scale balance? Why?

Focus: As you watch, notice the problem that the CyberSquad is trying to figure out. Write down the problem using numbers and symbols. See if you can solve it before they do. Did you use addition or subtraction at all?