Monday, June 22, 2009

Problem 308. Regular Nonagon or Enneagon, Midpoints, Side, Arc, Angle

Proposed Problem
Click the figure below to see the complete problem 308.

 Problem 308. Regular Nonagon or Enneagon, Midpoints, Side, Arc, Angle.
See also:
Complete Problem 308
Collection of Geometry Problems

Level: High School, SAT Prep, College geometry

2 comments:

  1. By problem # 307, angle (NOC) = 20 & angle (PNO)= 30. Hence, angle (NQO) = 30 - 20 = 10 deg. QED

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  2. Reference my proof for Problem 307 the external angle of the cyclic quadrilateral COPN is 70 hence aloha = 70 - 60 = 10

    Sumith Peiris
    Moratuwa
    Sri Lanka

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