Dividing Evenly a Quadrilateral II
What is this about?
A Mathematical Droodle


This applet requires Sun's Java VM 2 which your browser may perceive as a popup. Which it is not. If you want to see the applet work, visit Sun's website at http://www.java.com/en/download/index.jsp, download and install Java VM and enjoy the applet.


Buy this applet
What if applet does not run?

Explanation

|Activities| |Contact| |Front page| |Contents| |Geometry| |Store|

Copyright © 1996-2012 Alexander Bogomolny

It appears that the problem of bisecting the area of a quadrilateral ABCD by a line through a vertex (C below) has been proposed by Professor W. McWorter as a ruler and compass construction in 1964. In 2004, it has been used at the Rasor-Bareis-Gordon competition at the Ohio State University. The applet reflects Prof. McWorter's solution.


This applet requires Sun's Java VM 2 which your browser may perceive as a popup. Which it is not. If you want to see the applet work, visit Sun's website at http://www.java.com/en/download/index.jsp, download and install Java VM and enjoy the applet.


Buy this applet
What if applet does not run?

A line parallel to AC is drawn through either B (to the intersection with AD) or through D (to the intersection with AB.) CM is the median of either ΔCDE or ΔCBE. CM bisects the area of the relevant triangle and, where M falls inside a side of ABCD (AD or AB as the case may be), it also divides the area of quadrilateral ABCD. For the construction to go through, it needs to be shown that one of the two cases always takes place. One way of doing that is by following the previous construction: any line (in particular that parallel to AC) through the midpoint K of the base BD of ΔABD crosses one of the sides, either AB or AD. This point serves as the midpoint of the side opposite vertex C in one of the triangles CDE or CBE.

Area of Quadrilateral

|Activities| |Contact| |Front page| |Contents| |Geometry| |Store|

Copyright © 1996-2012 Alexander Bogomolny

 40620154

A math books store at a unique math study site. Shopping at the store helps maintain the site. Thank you.
Sites for teachers
Sites for parents
Terms of use
Awards
Interactive Activities

CTK Exchange
CTK Wiki Math
CTK Insights - a blog
Math Help
Games & Puzzles
What Is What
Arithmetic
Algebra
Geometry
Probability
Outline Mathematics
Make an Identity
Book Reviews
Stories for Young
Eye Opener
Analog Gadgets
Inventor's Paradox
Did you know?...
Proofs
Math as Language
Things Impossible
Visual Illusions
My Logo
Math Poll
Cut The Knot!
MSET99 Talk
Old and nice bookstore
Other Math sites
Front Page
Movie shortcuts
Personal info
Privacy Policy

Guest book
News sites

Recommend this site

Sites for parents

Education & Parenting

Search:
Keywords:

Google
Web CTK
Supported by
3wVentures