The 99 points of intersection presented here were collected during a year-long search for surprising concurrence of lines. For each example we find compelling evidence for the sometimes startling fact that in a geometric figure three straight lines, or sometimes circles, pass through one and the same point. Of course, we are familiar with some examples of this from basic elementary geometry - the intersection of medians, altitudes, angle bisectors, and perpendicular bisectors of sides of a triangle. Here there are many more examples - some for figures other than triangles, some where even more than three straight lines pass through a common point. The main part of the book presents 99 points of intersection purely visually, developed in a sequence of figures. In addition the book contains general thoughts on and examples of the points of intersection, as well as some typical methods of proving their existence.

A collection of surprising concurrences of lines with some typical methods for proving their existence.

About the Author
Hans Walser is lecturer at the Swiss Federal Instititute of Technology and the University of Basel.

Reviews
This book is highly recommended for geometers of all ages and a wide range of expertise. It would be an excellent resource for a course taught with Dynamic Geomeetry Software."" - Mary Coupland, Australian Mathematics Teacher



Book Information
ISBN 9780883855539
Author Hans Walser
Format Hardback
Page Count 168
Imprint Mathematical Association of America
Publisher Mathematical Association of America
Weight(grams) 357g
Dimensions(mm) 236mm * 156mm * 13mm