Showing posts with label Geometry Problems. Show all posts
Showing posts with label Geometry Problems. Show all posts

Thursday, October 15, 2026

Geometric Challenge

Problem 1627: Three Mutually Tangent Circles, Collinear Centers, and Curvilinear Incircle Radii Relations

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

In Problem 1627, we explore three mutually tangent circles with collinear centers and a common external tangent line. The challenge is to prove using synthetic similarity that the radii satisfy a geometric progression, and to establish the elegant radical and harmonic difference relations involving the radii of their curvilinear inscribed circles.
Explore the full theorem and illustrated diagram by clicking the image below.

Illustration of Geometry Problem 1627: Three Mutually Tangent Circles and Collinear Centers
Click for additional details and full diagram.

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 digital proofs (GeoGebra, Desmos).
Be the first to submit a formal solution for this 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.

Saturday, October 3, 2026

Geometric Challenge

Problem 1626: Triangle and Inscribed Rhombus Segment Lengths

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

In Problem 1626, we explore a triangle ABC with side lengths a, b, and c, containing an inscribed rhombus BDEF of side length d. Intersecting lines from the rhombus vertices form specific segments along the sides of the triangle. The challenge is to prove that the length of the segment GH can be elegantly expressed in terms of the triangle sides and the rhombus side length as GH = b (d/a + d/c - 1).
Explore the full theorem and illustrated diagram by clicking the image below.

Illustration of Geometry Problem 1626: Triangle and Rhombus Segments
Click for additional details and full diagram.

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 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.