How do you find the area of a heptagon?

The following two methods can find the area of a regular heptagon. These methods will not work on an irregular heptagon.

Multiply the length of one side by 7/4 and then by the cotangent of a 25 5/7 degree angle. Multiply the perimeter by the distance from the center to the middle of a side, then divide by two.

You must know the length of a side to calculate the area of a heptagon.

Area = n (s/2)^2 / tan( pi /n)

where n=7; s=side length

A septagon is a seven sided figure. Given a regular septagon (with seven sides of equal length), the formula for the area is 7/4 (a^2) * cot (180 degrees/7), where a is the length of one side.