Results 1 to 3 of 3
Like Tree1Thanks
  • 1 Post By johng

Math Help - Cyclic quadrilateral & tangential quadrilateral proof

  1. #1
    Newbie
    Joined
    Jan 2013
    From
    Croatia
    Posts
    24

    Cyclic quadrilateral & tangential quadrilateral proof

    My "geometry English" is not good so I hope you can understand from picture.

    Cyclic quadrilateral & tangential quadrilateral proof-screenshot_1.png
    I need to prove that EFGH is tangential. Angles DHS,DGS,CFS,AES are right angles. Thanks.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    earboth's Avatar
    Joined
    Jan 2006
    From
    Germany
    Posts
    5,830
    Thanks
    123

    Re: Cyclic quadrilateral & tangential quadrilateral proof

    Quote Originally Posted by kicma View Post
    My "geometry English" is not good so I hope you can understand from picture.

    Click image for larger version. 

Name:	Screenshot_1.png 
Views:	13 
Size:	17.4 KB 
ID:	30687
    I need to prove that EFGH is tangential. Angles DHS,DGS,CFS,AES are right angles. Thanks.
    Hello,

    I don't understand what is meant by your drawing. I've attached a sekant-tangent-quadrilateral:

    Cyclic quadrilateral & tangential quadrilateral proof-sehntang4eck.png

    Please tell us which point is your point S: The crosspoint of the red sekants or the midpoint of the inner circle k_i?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Super Member
    Joined
    Dec 2012
    From
    Athens, OH, USA
    Posts
    639
    Thanks
    257

    Re: Cyclic quadrilateral & tangential quadrilateral proof

    Hi,
    I think I understand your question. Here's a solution:

    Last edited by johng; April 18th 2014 at 01:01 PM.
    Thanks from kicma
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Cyclic quadrilateral
    Posted in the Geometry Forum
    Replies: 1
    Last Post: March 30th 2014, 05:38 PM
  2. Cyclic quadrilateral.
    Posted in the Geometry Forum
    Replies: 3
    Last Post: July 29th 2011, 04:01 AM
  3. cyclic quadrilateral ...
    Posted in the Geometry Forum
    Replies: 21
    Last Post: February 11th 2011, 07:10 AM
  4. Cyclic Quadrilateral
    Posted in the Geometry Forum
    Replies: 2
    Last Post: March 17th 2010, 01:09 AM
  5. Replies: 1
    Last Post: May 17th 2009, 04:12 AM

Search Tags


/mathhelpforum @mathhelpforum