Octadecagon Octadecagon An octadecagon (or octakaidecagon) or 18-gon is an eighteen-sided polygon. A "regular octadecagon" has a Schläfli symbol {18} and can be constructed as a quasiregular truncated enneagon, t{9}, which alternates two types of edges. As 18 = 2 × 3, a regular octadecagon cannot be constructed using a compass and straightedge. However, it is constructible using neusis, or an angle trisection with a tomahawk. The following approximate construction is very similar to that of the enneagon, as an octadecagon can be constructed as a truncated enneagon. It is also feasible with exclusive use of compass and straightedge. The "regular
How Many Billboards? Art Instead How Many Billboards? Art Instead How Many Billboards? Art Instead, was a large scale urban art exhibition in Los Angeles, California. The exhibition, which opened in February 2010, concurrently displayed 21 unique billboards created by various leading contemporary Californian artists. Organized by MAK Center director Kimberli Meyer and co-curated by Nizan Shaked and Dr. Gloria Sutton, the exhibition asked artists "to create a new work that critically responded to the medium of the billboard and interpreted its role in the urban landscape". Notable contemporary artist Martha Rosler and her son Josh Neufeld were among some of the commissioned artists. https://www.fastcompany.com/1559860/los-angeles-swaps-21-billboards-art