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The Angle-Angle (AA) Criterion for Two Triangles to Be Similar Lesson PlanThe Angle-Angle (AA) Criterion for Two Triangles to Be Similar Lesson Plan
Publisher
EngageNY
Resource Details
Curator Rating
Educator Rating
Not yet Rated
Grade
9th - 10th
Subjects
Math
1 more...
Resource Type
Lesson Plans
Audience
For Teacher Use
Duration
1 hr
Instructional Strategies
Guided Practice
2 more...
Technology
Presentation
Year
2015
Usage Permissions
Creative Commons
BY-NC-SA: 3.0
cc
Language
English, Arabic
Lesson Plan

The Angle-Angle (AA) Criterion for Two Triangles to Be Similar

Curated and Reviewed by Lesson Planet
This The Angle-Angle (AA) Criterion for Two Triangles to Be Similar lesson plan also includes:
  • Similarity, Proof, and Trigonometry - Module Overview (PDF)
  • Similarity, Proof, and Trigonometry - Module Overview (Doc)
  • The Angle-Angle (AA) Criterion for Two Triangles to Be Similar (Doc)
  • The Angle-Angle (AA) Criterion for Two Triangles to Be Similar (PDF)
  • The Angle-Angle (AA) Criterion for Two Triangles to Be Similar (Doc)
  • Assessment
  • Answer Key
  • Join to access all included materials

What do you need to prove triangles are similar? Learners answer this question through a construction exploration. Once they establish the criteria, they use the congruence and proportionality properties of similar objects to find missing sides. 

42 Views 25 Downloads
CCSS: Designed

Concepts

similar triangles, similarity, proportions

Additional Tags

math

Instructional Ideas

  • Incorporate modalities such as ang-legs for exploration in place of the constructions
  • Provide non-examples of similar triangles to allow for comparison

Classroom Considerations

  • Opening activity requires construction tools
  • Pupils must be able to solve proportions; review as necessary
  • The lesson continues from the first fourteen in a 36-part series

Pros

  • Takes a hands-on approach to determine criterion for similar triangles
  • Questioning encourages critical thinking

Cons

  • None

Common Core

HSG-SRT.A.2 HSG-SRT.A.3 HSG-SRT.B.5 HSG-MG.A.1 MP2 MP3 MP5

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