## anonymous 5 years ago Find the area of a regular octagon with a radius of 10 cm.

1. watchmath

The octagon forms 8 equal triangles each which angle $$360^\circ/8=45^\circ$$. Then the area of one of the octagon is $$8\cdot \frac{1}{2}\cdot 10^2\sin 45^\circ=200\sqrt{2}$$

2. anonymous

Thank you! I've had the hardest time finding a formula that makes sense.