Friday, August 26, 2011

Problem 661: Intersecting Circles, Centers, Secant, Parallelogram

Geometry Problem
Level: Mathematics Education, High School, Honors Geometry, College.

Click the figure below to see the complete problem 661.

 Online Geometry Problem 661: Intersecting Circles, Centers, Secant, Parallelogram.

1 comment:

  1. ∠ADB = (1/2) ∠AO’B (in circle O')
    = (1/2)[(1/2)∠AOB] (in circle O)
    = (1/2) ∠AOC (in circle O)
    = ∠AEC ( ,, )
    = ∠CFB ( ,, )
    (AO'O and BO'O are congruent isosceles ∆les,
    ∠AO'O = ∠BO'O, arc AC = arc BC)
    So DE∥FC, DF∥AC and DECF is a parallelogram

    ReplyDelete