Tagged: triangles

September 2, 2025

A Beautiful Application of Shearing

I must admit that I am addicted to triangle shearing problems . I’ve written about them before, and will be revisiting them soon in my City College geometry class. I mention this because several weeks ago, I encountered a problem in the LinkedIn feed of mathematics educator James Tanton that made me wonder whether a...

Geometry / Math Software

September 26, 2024

Some Triangle Shearing Investigations

When I taught a geometry methods course at City College last fall, I devoted an entire class to investigating area. We focused on problems where triangles were sheared, transforming into new triangles, but maintaining their area. The two Web Sketchpad activities that follow introduce shearing and present a problem with a surprising result that can...