Illuminations: The Plus Sign and Triangle

Using a scheme similar to the one in the Rectangle lesson of this unit, students will further explore the concepts of identity, inverse, and commutative and associative properties.

Students investigate and analyze moves performed with a plus sign, and an online activity is available to help students with this investigation.


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Algebra & Pre-Algebra
Middle School, Educator

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Illuminations (National Council of Teachers of Mathematics)

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