A nice way to construct an ellipse or hyperbola, inspired by the PCMI summer 15, problem set 7, questions 14 and 18. [url]http://mathforum.org/pcmi/hstp/sum2015/morning/darryl/day07.pdf[/url] Thanks to Tina Cardone, Bowen Kerins and Darryl Yong.
More GeoGebra at [url]bit.ly/mh-ggb[/url]