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Right Triangles Inscribed in Circles II Lesson PlanRight Triangles Inscribed in Circles II Lesson Plan
Publisher
Illustrative Mathematics
Resource Details
Curator Rating
Educator Rating
Not yet Rated
Grade
9th - 10th
Subjects
Math
1 more...
Resource Types
Activities & Projects
1 more...
Audience
For Teacher Use
Duration
45 mins
Instructional Strategies
Demonstration
2 more...
Technology
Calculator
Usage Permissions
Creative Commons
BY-NC-SA: 4.0
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Lesson Plan

Right Triangles Inscribed in Circles II

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This Right Triangles Inscribed in Circles II lesson plan also includes:
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  • Teacher Reference
  • Worksheet
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So many times the characteristics of triangles are presented as a vocabulary-type of lesson, but in this activity they are key to unraveling a proof. A unique attack on proving that an inscribed angle that subtends a diameter must be a right angle uses properties of midsegments and similar triangles. The proof using quadrilaterals is also outlined, for interested parties. Leading questions help guide learners through the proof, while still leaving the structure open for development.

15 Views 12 Downloads
CCSS: Designed

Concepts

inscribed, triangles, right angles, diameter, radius, proofs

Additional Tags

math

Instructional Ideas

  • Suggested differentiations include amending or removing specific instruction hints
  • Great activity for extending existing skill practice on circle properties, or showing application of triangle characteristics

Classroom Considerations

  • May need some support or review of midsegments and other triangle properties if that lesson is not recent

Pros

  • Clear application of triangle properties that can often seem isolated and not useful
  • Excellent open-ended question to help develop mathematical writing and logic skills

Cons

  • Student worksheet not separated from teaching notes and answer key

Common Core

HSG-CO.A.2

View 38,632 other resources for 9th - 10th Grade Math

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