[tex]l _{triunghi.echilateral}=R \sqrt{3}=4\sqrt{3}cm \\ a _{triunghi.echilateral}= \frac{R}{2} = \frac{4}{2} =2cm \\ l _{patrat}=R \sqrt{2}=4\sqrt{2}cm \\ a _{patrat}= \frac{R \sqrt{2} }{2} = \frac{4\sqrt{2}}{2} =2\sqrt{2}cm \\ \\ A= \frac{ l^{2} \sqrt{3} }{4} =8 \sqrt{3} cm \\ l ^{2} = \frac{4*8 \sqrt{3} }{\sqrt{3} } =32 \\ l= \sqrt{32} =4 \sqrt{2} cm \\ l =R \sqrt{3} \\ R= \frac{l \sqrt{3} }{3}= \frac{4 \sqrt{6}}{3}cm \\ a = \frac{R}{2} =\frac{2 \sqrt{6}}{3}cm[/tex]
