enneaegseid
Enneaegseid, also known as enneaheptagon, is a polygon with nine sides and seven diagonals. It is a type of nonagon, which is any polygon with nine sides. The term "enneaegseid" is derived from the Greek words "ennea," meaning nine, and "gon," meaning angle. Enneaegseid is a regular polygon, meaning all its sides and angles are equal. The interior angle of a regular enneaegseid is approximately 140 degrees, and the exterior angle is approximately 40 degrees. The area of a regular enneaegseid can be calculated using the formula (9/4) * a^2 * cot(π/9), where "a" is the length of a side. Enneaegseid is a less common polygon, but it has been studied in geometry and mathematics for its unique properties. It is often used in architectural designs and art due to its symmetrical and aesthetically pleasing shape.