A 90-sided polygon.
Enneacontagon
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Cite this as:
Weisstein, Eric W. "Enneacontagon." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Enneacontagon.html
A 90-sided polygon.
Weisstein, Eric W. "Enneacontagon." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Enneacontagon.html