Dimilafy

Ny dimilafy (Grika taloha: πεντάγωνον) dia karazana endrika iray manana lafy dimy. Antsoina hoe dimimira izay dimilafy manana lafy dimy mitovy halava.

Dimimira

Ny velaran'ny dimimira manana halavan-dafy tokana ihany dia :

A={\frac {t^{2}{\sqrt {25+10{\sqrt {5}}}}}{4}}={\frac {5t^{2}\tan(54^{\circ })}{4}}\approx 1.720477401t^{2}.