SOLUTION: I am making a seven sided shape,each side has a measurement of 30 "what is the total ground area in square yards.

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Question 980109: I am making a seven sided shape,each side has a measurement of 30 "what is the total ground area in square yards.
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
I am making a seven sided regular polygon, each side has a measurement of 30 yd.
What is the total ground area in square yards?
Each interior angle using formula %28%28n-2%29%2A%22180%B0%22%29%2Fn%22%22=%22%22%28%287-2%29%2A%22180%B0%22%29%2F7128%264%2F7°.  In the second figure that angle is divided
in half so it's 64%262%2F7°.  The 30 yd is also divided in half, so each
is 15 yd.
 





By the right triangle on the left,

tan%2864%262%2F7%29%22%22=%22%22h%2F15
15%2Atan%2864%262%2F7%29%22%22=%22%22h

Then the area of each of these 7 isosceles triangles



is found by the formula 

A=expr%281%2F2%29bh=expr%281%2F2%29%2830%29%2815%2Atan%2864%262%2F7%29%29

We multiply that by 7 and get

7%2Aexpr%281%2F2%29%2830%29%2815%2Atan%2864%262%2F7%29%29%22%22=%22%22matrix%281%2C3%2C3270.5212%2Csquare%2Cyards%29

Edwin