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Triangles with one angle equal to 60 degrees

Published online by Cambridge University Press:  23 January 2015

Shailesh A. Shirali
Shailesh A. Shirali*
Affiliation:
Rishi Valley School (KFI), Rishi Valley 517 352, Andhra Pradesh, Indiae-mail:shailesh.shirali@gmail.com
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Extract

Triangles with a 60° angle possess many interesting geometric properties. Here is a well-known example: In ΔABC with incentre I, let the rays meet the sides AC, AB at B1, C1 respectively. If ∠B = ∠C, then IB1 = IC1, trivially. Does the converse implication hold? No – the same condition holds when ∠A = 60° (irrespective of the relation between ∠B and ∠C). In this article we study some more properties possessed by triangles having a 60° angle.

Type
Articles
Information
The Mathematical Gazette , Volume 95 , Issue 533 , July 2011 , pp. 227 - 234
Copyright
Copyright © The Mathematical Association 2012

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