Odpowiedź :
[tex]Obw = 12 \ cm\\i \\ Obw = 3a\\P = ?\\\\3a = 12 \ cm \ \ /:3\\\\a = 4 \ cm\\\\\\P = \frac{a^{2}\sqrt{3}}{4}= \frac{4^{2}\sqrt{3}}{4}=4\sqrt{3} \ cm^{2}[/tex]
[tex]Obw = 12 \ cm\\i \\ Obw = 3a\\P = ?\\\\3a = 12 \ cm \ \ /:3\\\\a = 4 \ cm\\\\\\P = \frac{a^{2}\sqrt{3}}{4}= \frac{4^{2}\sqrt{3}}{4}=4\sqrt{3} \ cm^{2}[/tex]