Families of Four-Point Touching Isosceles Triangles
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This Demonstration shows four-point touching families of 
of isosceles triangles. The task is to find parameters so that the triangles form a four-point touching family.
Contributed by: Izidor Hafner (May 2019)
Open content licensed under CC BY-NC-SA
Snapshots
Details
A family 
is said to be 
-touching provided each element of 
has a nonempty intersection with precisely 
other elements of 
. A 
-touching family 
is said to be point-
-touching if any two touching sets have only a single common point [1].
[1] B. Grünbaum, "Families of Point-Touching Squares," Geombinatorics, 12(4), 2003 pp. 167–174. (Mar 27, 2019) sites.math.washington.edu/~grunbaum/Familiesofpointtouchin.pdf.
Permanent Citation
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