Saturday, October 1, 2016

Geometry Problem 1269 Triangle, Incircle, Incenter, Inscribed Circle, Tangency Points, Perpendicular, 90 Degrees, Angle Bisector

Geometry Problem. Post your solution in the comment box below.
Level: Mathematics Education, High School, Honors Geometry, College.

Click the figure below to view more details of problem 1269.


Geometry Problem 1269 Triangle, Incircle, Incenter, Inscribed Circle, Tangency Points, Perpendicular, 90 Degrees, Angle Bisector.

3 comments:

  1. connect OC, <BDA1 = <COA1, so OCDA1 is on the same circle. <ODC = 90 = <OA1C =<AA1C

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  2. < DEB = 90-B/2 and < A1AE = A/2 so
    < EA1A = 90-B/2 - A/2 = C/2.

    But < OCD = C/2 hence OCDA1 is concyclic

    Therefore <OA1C = <ODC = 90

    Sumith Peiris
    Moratuwa
    Sri Lanka

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