SOLUTION: ok the problem i need help on if find the exact area of a regular dodecagon inscribed in circle with the radius R

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Question 139977This question is from textbook dicovering geometry
: ok the problem i need help on
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find the exact area of a regular dodecagon inscribed in circle with the radius R This question is from textbook dicovering geometry

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
A regular dodecagon has 12 equal sides.
The radius of the dodecagon is equal to the radius of the circumscribed circle.
Using the formula for the area of a regular polygon of n sides and having a radius R:
A+=+%281%2F2%29nR%5E2Sin%28360%2Fn%29 Substitute n = 12 and simplify.
A+=+%281%2F2%29%2812%29R%5E2Sin%28360%2F12%29
A+=+6R%5E2Sin%2830%29
A+=+6R%5E2%280.5%29
A+=+3R%5E2...and since the value of R is not provided, this is as far as we can go!