triangle mathematics Actions Share Share Share to social media Facebook Twitter URL https://www.britannica.com/science/triangle-mathematics Share Share Share to social media Facebook Twitter URL https://www.britannica.com/science/triangle-mathematics Written by Michael McDonough Michael McDonough was a media team intern at Encyclopaedia Britannica. He is expected to graduate in 2023 from Northwestern University. Michael McDonough Fact-checked by The Editors of Encyclopaedia Britannica Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors. The Editors of Encyclopaedia Britannica Last Updated: Jun 12, 2024 • Article History Table of Contents Key People: Heron of Alexandria (Show more) triangle, in geometry, a three-sided polygon. Triangles are formed by three line segments, sometimes called edges, whose end points intersect at points known as the vertices. The seemingly simple shape has countless properties discovered over thousands of years of study. The following article concerns triangles in Euclidean geometry; the features of non-Euclidean triangles, such as spherical triangles and hyperbolic triangles, do not necessarily adhere to the following descriptions. Triangles are typically named after their vertices. For example, the common name ΔABC denotes a triangle with vertices A, B, and C. Interior angle names and measurements are often represented by the ...(100 of 989 words)

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