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From the Fun Fact files, here is a Fun Fact at the Easy level:

Morley's Theorem

Figure 1
Figure 1

Take any triangle. Mark the 3 points which are the intersections of adjacent angle trisectors. No matter what triangle you start with, these 3 points will form an equilateral triangle!

Presentation Suggestions:
Draw a picture and invite students to draw their own triangle on a sheet of paper and follow along.

The Math Behind the Fact:
This is yet another surprising fact from geometry. Can you think of a proof?

How to Cite this Page:
Su, Francis E., et al. "Morley's Theorem." Math Fun Facts. <>.

Subjects:    geometry
Level:    Easy
Fun Fact suggested by:   Jorge Aarao
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