Este vorba de un hexagon regulat inscris in cerc !
[tex] *\;diametrul \,cercului =D = 2*R=12cm \;\rightarrow\;R=6cm\;;\\
**\;l_6=latura\;hexagonului\;;\;l_6=R=6cm\;;\\
***\;A_{cerc}=\pi\cdot{R}^2=36\pi\,{cm}^2\;;\\
P=6*6=36cm\;\\
****\;A_{hexagon}=\frac{6\cdot{l}^2\sqrt3}{4}=\frac{6*36*\sqrt3}{4}=54\sqrt3\,cm^2\;;\\
A_{sectiunii \,eliminata}\,\approx\,36*3,14\,-\,54*1,73=19,62\,cm^2\,
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