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Geometry · Polygons

Octagon side 1

8,\ 1

Step by step

  1. \text{interior angle} = \frac{(n-2)\cdot 180^\circ}{n} = 135^\circ

    A regular 8-gon.

  2. P = n s = 8

    Perimeter.

  3. a = \frac{s}{2\tan(\pi/n)} = \frac{1}{2} + \frac{\sqrt{2}}{2} \approx 1.2071

    Apothem (centre to the middle of a side).

  4. A = \tfrac{1}{2} P a = 2 + 2 \sqrt{2} \approx 4.8284

    Area = half the perimeter times the apothem.

Reveal the answer
A = 2 + 2 \sqrt{2} \approx 4.8284