## Saturday, September 5, 2015

### Pythagorean theorem Day - a^2 + b^2 = c^2

One week from today is Pythagorean Theorem Day, 9/12/15.

a2 + b2 = c2

92 + 122 = 152

So it is time to prepare.  Prior Planning Prevents Poor Performance.

Traditionally, each math student in a school will choose a different proof of the Pythagorean Theorem.  Then when they go to their math class they tell their teacher, professor, or math guru that they were doing some research on the Pythagorean theorem and found a very interesting proof that they would like to share with the class.  How could a teacher, professor of math guru turn down a request like that?  By the time each student is done showing a different proof there will not be any time left for a quiz or test.

Pythagoras (I think his first name was Pete) did not invent the Pythagorean Theorem.  We know that this theorem was known to the Babylonians and Egyptians who came along years before Pythagoras.

Euclid shows a proof of the Pythagorean Theorem in his books "The Elements".  His proof is known as the "windmill" proof.  http://www.cs.uleth.ca/~holzmann/notes/pythagoras.pdf

President James Garfield is known to produce a new proof of the Pythagorean Theorem.  http://math.kennesaw.edu/~sellerme/sfehtml/classes/math1112/garfieldpro.pdf

Elisha Scott Loomis published the book "The Pythagorean Proposition" in 1968 showing 370 different proofs of the Pythagorean Theorem.A PDF version of this book is available at: http://files.eric.ed.gov/fulltext/ED037335.pdf

Alexander Bogomolny, at Cut-the-Knot.com, has a well documented and researched list of 111 proofs of the Pythagorean Theorem - and adds new proofs has he finds them.  http://www.cut-the-knot.org/pythagoras/

So you now have instant access to many different proofs to use on Pythagorean Theorem Day.

Please make the most out of this Pythagorean Theorem Day.  The next three Pythagorean Theorem Days will occur on
`8/15/17, 12/16/20, and 7/24/25.`
` `
`Have a Happy Pythagorean Theorem Day,`
` `
`David `
`(The Math Buddha - `
`Showing a pathway to Mathematical Enlightenment)`
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`Wait - Opps - 9/12/15 is a Saturday.  Never mind.`