Every Triangle is the Shadow of an Equilateral Triangle
Publication Date
Spring 4-16-2025
Presentation Length
20 minutes
College
College of Sciences & Mathematics
Department
Math and Computer Science, Department of
Student Level
Undergraduate
SPARK Category
Scholarship
Faculty Advisor
Adam Cartisano
WELL Core Type
Intellectual Wellness
Metadata/Fulltext
Fulltext
SPARK Session
Geometry Topic
Presentation Type
Talk/Oral
Summary
The Euler line of a triangle is a classical object with an interesting optical illusion: As one translates the vertices of the triangle, the Euler line appears to "pop" into 3D space! The goal of this project is to formalize that intuition by realizing the triangle as the projected image of an equilateral triangle in R^3, where the projection maps the normal line through its centroid to the Euler line of the image.
In this presentation, we will motivate the problem and showcase some of the geometry using GeoGebra activities, and we will prove some partial results: Every triangle in R^2 is the orthogonal projection of an equilateral triangle in R^3, and this projection takes centroids to centroids. We also have a procedure for finding an equilateral triangle which is in perspective with an arbitrary triangle in R^2.
Recommended Citation
Ruiz, Elena and Pittman, Chase, "Every Triangle is the Shadow of an Equilateral Triangle" (2025). SPARK Symposium Presentations. 293.
https://repository.belmont.edu/spark_presentations/293