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Tangent to a Circle From a Point ActivityTangent to a Circle From a Point Activity
Publisher
Illustrative Mathematics
Resource Details
Curator Rating
Educator Rating
Not yet Rated
Grade
9th - 10th
Subjects
Math
1 more...
Resource Types
Activities & Projects
2 more...
Audience
For Teacher Use
Duration
10 mins
Instructional Strategies
Demonstration
2 more...
Technology
Scientific Equipment
Presentation
Usage Permissions
Creative Commons
BY-NC-SA: 4.0
cc
Activity

Tangent to a Circle From a Point

Curated and Reviewed by Lesson Planet
This Tangent to a Circle From a Point activity also includes:
  • Answer Key
  • Worksheet
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Learners see application of construction techniques in a short but sophisticated problem. Combining the properties of inscribed triangles with tangent lines and radii makes a nice bridge between units, a way of using information about both to describe a situation. A great quickie problem to help remind learners that just because a property looks evident doesn't mean it can just be stated without proof.

10 Views 8 Downloads
CCSS: Designed

Concepts

circles, tangent, inscribed, radius, right angles

Additional Tags

math

Instructional Ideas

  • Use before and after teaching construction techniques as a motivator or reward
  • Use as a refresher problem on circle or tangent properties as part of a larger review

Classroom Considerations

  • Student task is not separated from teacher notes and solution key

Pros

  • Elegant solution pulls from both triangle and circle properties to reach conclusions
  • Good example of using mathematical rigor to defend and prove something that seems evident from a diagram

Cons

  • Though introduced as a construction problem, no actual construction is performed—just using definitions to describe what is shown in a diagram
  • The circles are named C and D, but only diagrammed by the centers O and M, making them hard to follow through the explanations

Common Core

HSG-C.A.4

View 38,618 other resources for 9th - 10th Grade Math

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