# The Relationship between the Nine-Point Circle, the Circumscribed Circle and the Inscribed Circle of Archimedes’ Triangle

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Yuporn Rimcholakarn

## Abstract

The purpose of this research was to study the relationship between the Nine-Point Circle and the Circumscribed circle of Archimedes’ triangle, and the relationship between the Nine-Point circle and the Inscribed circle of Archimedes’ triangle. The results were that the radius of the Nine-Point Circle of Archimedes’ triangle is half the radius of the Circumscribed circle of Archimedes’ triangle, and the Nine-Point circle and the Inscribed circle of Archimedes’ triangle touch internally.

Keywords: Archimedes’ triangle, Nine-Point circle, Circumscribed circle of triangle, Inscribed circle of triangle

## References

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Section
Research Articles

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How to Cite
RIMCHOLAKARN, Yuporn. The Relationship between the Nine-Point Circle, the Circumscribed Circle and the Inscribed Circle of Archimedes’ Triangle. Naresuan University Journal: Science and Technology (NUJST), [S.l.], v. 26, n. 3, p. 63-79, sep. 2018. ISSN 2539-553X. Available at: <http://www.journal.nu.ac.th/NUJST/article/view/Vol-26-No-3-2018-63-79>. Date accessed: 21 jan. 2021. doi: https://doi.org/10.14456/nujst.2018.10.