Texas Instruments TI-73 Manual Book page 24

6. Start once more at the top peg and draw a 12-sided regular
polygon by placing a vertex at every peg. 12×1=12.
You now have one example of each regular polygon that can
be drawn around a 12-peg board.
7. Make sure the cursor is on the top peg, and press the E
key. The first polygon becomes selected.
8. Press  to view the polygons in succession.
Notice that for each polygon, the number of sides × the number
of pegs from vertex-to-vertex = 12. Consider the number of
regular polygons possible on a 24-peg board.
TI-73 Geoboard Page 24