geometry regular polygon
posted by Skye .
a=?
s=10.5cm
A= 19,887.5cm squared
Pentagon
A=asn/2
19,887.5cm=a*10.5*5/2
39775=52.5a
a=757.61cm?
am i correct?
regular nonagon
a=9.6cm
A=302.4cm squared
find perimeter thanks!

302.4cm^2
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