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The triangles {t,t,T} have side lengths x = tT = 1 resp. C = tt = 1.049668. The enneagons are regular and unit-edged. – Only the edge types x and C of the description below survive. The pseudo edges A and B are chords of the enneagons. Edge type C is the edge size of the squares.

Incidence matrix according to Dynkin symbol

xA3Bo4oC&#zx – → A = x(9,3) = sin(60°)/sin(20°) = 2.532089
                 B = x(9,2) = sin(40°)/sin(20°) = 1.879385
                 C = tt = 1.049668

o.3o.4o.    | 24  * |  1  2  0 | 2  1 0  [T,9,9]
.o3.o4.o    |  * 24 |  0  2  2 | 1  2 1  [t,4,t,9]
------------+-------+----------+-------
x. .. ..    |  2  0 | 12  *  * | 2  0 0
oo3oo4oo&#x |  1  1 |  * 48  * | 1  1 0
.. .. .C    |  0  2 |  *  * 24 | 0  1 1
------------+-------+----------+-------
xA3Bo ..&#x |  6  3 |  3  6  0 | 8  * *  {9}
.. .. oC&#x |  1  2 |  0  2  1 | * 24 *  {(t,t,T)}
.. .o4.C    |  0  4 |  0  0  4 | *  * 6  C-{4}