Pythagorean Day

You may have heard of Pi Day (March 14) to celebrate the ratio of a circle’s circumference to its diameter or e day (February 7) to celebrate Euler’s constant, but have you heard of Pythagorean Day?

Pythagorean Day occurs when the digits in the date satisfy the Pythagorean Theorem. Recall that the Pythagorean Theorem states that in any right triangle with sides a and b and hypotenuse c, it is true that a² + b² = c². This year, Pythagorean day is August 15, 2017 because the digits 8, 15, and 17 satisfy the Pythagorean Theorem: 8² + 15² =17².

Now that you know, how will you celebrate Pythagorean Day? Here are some fun ideas:

  • Throw a triangle party! Make and eat triangle-shaped foods, decorate with triangles, and play games such as seeing who can list the most Pythagorean triples.
  • Watch a short video of a conceptual demonstration of the Pythagorean Theorem.
  • Make your own proof of the Pythagorean Theorem.
  • Listen to a fun song about the Pythagorean Theorem.

The next Pythagorean Day will not happen until December 16, 2020 (12² + 16² = 20²). Have a happy Pythagorean Day!



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