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Informal Proof of AA Criterion for Similarity Lesson PlanInformal Proof of AA Criterion for Similarity Lesson Plan
Publisher
EngageNY
Resource Details
Curator Rating
Educator Rating
Not yet Rated
Grade
8th
Subjects
Math
3 more...
Resource Types
Assessments
5 more...
Audience
For Teacher Use
Duration
45 mins
Instructional Strategies
Collaborative Learning
3 more...
Technology
Ed Software
Year
2015
Usage Permissions
Creative Commons
BY-NC-SA: 3.0
cc
Language
English, Arabic
Lesson Plan

Informal Proof of AA Criterion for Similarity

Curated and Reviewed by Lesson Planet
This Informal Proof of AA Criterion for Similarity lesson plan also includes:
  • Informal Proof of AA Criterion for Similarity (Doc)
  • Informal Proof of AA Criterion for Similarity (PDF)
  • Informal Proof of AA Criterion for Similarity (Doc)
  • Grade 8 Module 3: Teacher Materials
  • Grade 8 Module 3: Student Materials
  • Grade 8 Module 3: Copy Ready Materials
  • Math Fluency Support for Grades 6-8
  • Answer Key
  • Join to access all included materials

What does it take to show two triangles are similar? The 11th segment in a series of 16 introduces the AA Criterion for Similarity. A discussion provides an informal proof of the theorem. Exercises and problems require scholars to apply the theorem to justify whether two given triangles are similar.

10 Views 3 Downloads
CCSS: Designed

Concepts

similar triangles, similarity, geometric proofs, proofs

Additional Tags

math

Instructional Ideas

  • Incorporate using geometry software to get more precise measurements
  • Have individuals determine the transformations that would show their two drawn triangles are similar

Classroom Considerations

  • Class members should be comfortable with the Fundamental Theorem of Similarity

Pros

  • Some problems require more than AA to prove the similarity, they also require the Triangle Sum Theorem
  • The answer key provides sample justifications

Cons

  • None

Common Core

8.G.A.5 MP3

View 18,996 other resources for 8th Grade Math

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