Showing posts with label arbelo. Show all posts
Showing posts with label arbelo. Show all posts

Sunday, May 3, 2026

Geometric Challenge

1618 Geometry Problem: Altitudes and Semicircles in Harmony

Share your proof or solution in the comments below.
Target Audience: K-12, Honors Geometry, and College Mathematics Education.

Uncover the mathematical elegance hidden within heritage. In Problem 1618, we transition to the "Sacred Geometry" of circular systems. This challenge explores the sophisticated interplay of semicircles and diameters to reveal a striking set of concyclic points, reminiscent of the intentional alignments found in Incan architecture.
Explore the full theorem and illustrated diagrams by clicking the image below.

Illustration of Geometry Problem 1618: Machu Picchu Heritage
Click for additional details and full diagram.

Proposed Solution
We invite students, teachers, and math enthusiasts to share their insights. This challenge involves altitudes and circular properties that can be unlocked using synthetic geometry.

How to contribute:
Post your step-by-step proof in the comments below. Feel free to:
  • Describe the theorems applied.
  • Share a link to your dynamic construction (GeoGebra, Desmos).
Be the first to submit a formal solution for this heritage-themed problem!
Ready to contribute?
Please use the box below to Enter your Comment or Solution. You can use plain text or provide links to your digital proofs.

Sunday, May 31, 2009

Problem 295: Archimedean Twin Circles, Arbelos, Semicircles, Harmonic Mean, Radii, Perpendicular

Proposed Problem
Click the figure below to see the complete problem 295 about Archimedean Twin Circles, Arbelos, Semicircles, Harmonic Mean, Radii, Perpendicular, Diameter.

 Problem 295: Archimedean Twin Circles.
See also:
Complete Problem 295
Collection of Geometry Problems

Level: High School, SAT Prep, College geometry

Sunday, December 21, 2008

Archimedes' Arbelos and Square

Dynamic Geometry Software. Step-by-Step construction, Manipulation, and animation
In the figure, a circle D is inscribed in the arbelos ABC (AB, BC and AC are semicircles), prove that ELBK is a square.


Archimedes' Arbelos and Square.
Continue reading at:
gogeometry.com/geometry/archimedes_arbelo_circle_square.htm

Tuesday, December 16, 2008

Archimedes' Book of Lemmas, Proposition #6

Arbelos
Exercise your brain. Archimedes wrote the "Book of Lemmas" more than 2200 years ago. Solve the proposition #6 (high school level) and lift up your geometry skills.


Archimedes' Book of Lemmas #6.
Continue reading at:
gogeometry.com/ArchBooLem06.htm

Archimedes' Book of Lemmas, Proposition #5

Problem 644: Arbelos, Archimedean Twins
Exercise your brain. Archimedes wrote the "Book of Lemmas" more than 2200 years ago. Solve the proposition #5 (high school level) and lift up your geometry skills.


Archimedes' Book of Lemmas #5.
Continue reading at:
gogeometry.com/ArchBooLem05.htm

Archimedes' Book of Lemmas, Proposition #4, Arbelos

Problem 643
Exercise your brain. Archimedes wrote the "Book of Lemmas" more than 2200 years ago. Solve the proposition #4 (high school level) and lift up your geometry skills.


Archimedes' Book of Lemmas #4.
Continue reading at:
gogeometry.com/ArchBooLem04.htm