Geometry Musings #5 Triangle Incenter


This morning I decided to demonstrate how to use a compass and straight rule to find the incenter of a triangle.

This is a relatively easy task, especially given this rather cool way of bisecting an angle.

To construct this diagram, simly draw out a triangle:


Draw two concentric circles on two vertices:


Join each alternate segment like so:


Draw a line that from the vertex through the intersection:


Where they meet is the incenter. (incentre for UK?!)

Then colour it in for a laugh:


Anscombe’s Quartet

Anscombe’s quartet comprises four datasets that have nearly identical simple statistical properties, yet appear very different when graphed. Each dataset consists of eleven (x,y) points. They were constructed in 1973 by the statistician Francis Anscombe to demonstrate both the importance of graphing data before analyzing it and the effect of outliers on statistical properties”