Geogebra - Sam Hartburn

Excircles and excentres

The incircle of a triangle is fairly well known as the circle inscribed in the triangle – it’s tangent to each of the three sides, which means that it touches each one but doesn’t cross any of them. But did you know that triangles have three more circles that are (sort of) tangent to all…

May 16, 2024

The Nine Point Centre

How many centres do you think a triangle has? There are more than you might think. Maybe you learned about a few at school – the centroid, incentre and circumcentre are the classic ones that most people learn. But there are a few (actually, more than a few) more than that.

April 26, 2024

Is a Shape With 1000 Sides the Same as a Circle?

I recently found out about a shape I’d never heard of before: a chiliagon.

August 14, 2023

#DigitalGeometrySketchbook Days 21 to 30

Throughout the month of June 2021 I created a daily maths art piece, each one using different software or different techniques, as part of the #GeometrySketchbook challenge on Twitter. As mine was all digital artwork, I used the #DigitalGeometrySketchbook tag. Here are the results of days 21 to 30.

August 11, 2021

#DigitalGeometrySketchbook Days 11 to 20

Throughout the month of June 2021 I created a daily maths art piece, each one using different software or different techniques, as part of the #GeometrySketchbook challenge on Twitter. As mine was all digital artwork, I used the #DigitalGeometrySketchbook tag. Here are the results of days 11 to 20.

July 10, 2021

#DigitalGeometrySketchbook Days 1 to 10

Throughout the month of June 2021 I created a daily maths art piece, each one using different software or different techniques, as part of the #GeometrySketchbook challenge on Twitter. As mine was all digital artwork, I used the #DigitalGeometrySketchbook tag. Here are the results of days 1 to 10.

July 3, 2021