FE 'tkGooie' UtilitiesTk script CODE of some'MATHed'educational utilities(FE = Freedom Environment) 
A hint at the method of proof. D and E mark a square and a rectangle with equal areas. 
FE Home Page > FE Downloads Page > FE 'tkGooies' Description Page > This Page
! Preliminary ! Many more 'tkGooies' matheducation scripts may be added
 and the scripts here may be revised occasionally.
< Go to CodeLinks List, below. >
(SKIP THE INTRODUCTION)
OVERVIEW of 'MATHed'  in the FE 'tkGooies' system : A description of the FE 'tkGooies' system is available via a 'tkGooies' Description page. That page points out that the 'tkGooies' are a collection of utilities in categories (toolchests) such as
Just below is a list of links to pages that present the source code of a collection of the 'MATHed' Tk scripts in the FE 'tkGooies' system. Many of these 'MATHed' 'tkGooie' scripts are based on theorems in plane geometry.
Some sources (books, etc.) that give ideas for 'MATHed' (math education) projects are shown in a section at the bottom of this page. These sources include equations, methods, and, in some cases, code. 
List of Links to pages that present the CODE of 'MATHed' 'tkGooie' scripts:
The following mathproofsanddemosinTkGUI's are on a 'todo' list:
Some mathrelated Tk GUI scripts may be put in another category  such as an 'IMAGEanimations' subtoolchest of the 'IMAGEtools' toolchest:
 OR in a 'PHYSICStools' toolchest: Other mathrelated Tk GUI scripts can be seen on the ODEtools page, where ODE = Ordinary Differntial Equations. End of List of CodeLinks. 
How the code samples are presented : Use the listoflinks (above) to go directly to web pages that contain source code along with codedescriptions and screenshots. The Tk script files (and other auxiliary files, if any) are in text files that can be downloaded to your computer and implemented. To download, simply 'rightclick' on a text link and, in a popup window of your web browser, choose an option such as 'Save Link Target As ...'. 
Some SOURCES (books, etc.) for 'MATHed' coding projects:Many ideas for 'mathed' projects can be found in books that are meant to 'popularize' math and bring 'math surprises' to the general public  for example, books by mathpopularizers who have a Wikipedia page:
Other authors Some books by other authors that provide 'food' for many other Tk GUI projects are as follows.
Some WebSite Sources Some free ebooks may be available from freebookcentre.net (no registration required!! no attempts to keep you on their web pages!! no annoying popups!! in 2016)  in the areas of Mathematics and Physics  in particular in the areas of
A similar 'free ebooks' site is at ebooksdirectory.com. See the Mathematics and SciencePhysics categories. Some 'free ebooks' and 'free HTML sites' in the math and physics categories are at physicsdatabase.com. At 'openlibrary.org', you can use the Search field at the bottom of the math and physics pages to find books on specific topics. You can sort the results by 'most recent' (newest) or 'first published' (oldest). Also, see the Mathematics and Physics 'bookshelves' on the Science Bookshelf page of gutenberg.org  for some classic volumes (generally more than 80 years old).
For more sources of ideas for 'mathed' projects, here is a page of LINKS to math web sites which includes links to mathnews sites, mathblog sites, mathforum sites, mathhistory sites, etc. And here is a page of LINKS to math edocuments on the web organized into categories such as Geometry, Number Theory, Algebra, Analysis (Calculus), Applied Math, Numerical Analysis, etc. Still more ideas for 'mathed' projects may be found via this page of LINKS to sites on scienceengineering topics. As an alternative to the several 'LINKS' sites above, here is a page that offers quick 'directaccess' to math eDocs  'in the public domain', mostly PDF files. 
Bottom of the Links to FE 'tkGooies' Code  'MATHed' group page.
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