Odpowiedź:
[tex]h=10cm\\\\h=\frac{a\sqrt{3}}{2}\\\\10=\frac{a\sqrt{3}}{2}\ \ /\cdot2\\\\20=a\sqrt{3}\\\\a\sqrt{3}=20\ \ /:\sqrt{3}\\\\a=\frac{20}{\sqrt{3}}=\frac{20}{\sqrt{3}}\cdot\frac{\sqrt{3} }{\sqrt{3}}=\frac{20\sqrt{3}}{3}\\\\\\P=\frac{a^2\sqrt{3}}{4}=\dfrac{(\frac{20\sqrt{3}}{3})^2\cdot\sqrt{3}}{4}=\dfrac{\frac{20^2\cdot(\sqrt{3})^2 }{3^2}\cdot\sqrt{3}}{4}=\dfrac{\frac{400\cdot\not3^1}{\not9_{3}}\cdot\sqrt{3} }{4}=\dfrac{\frac{400}{3}\cdot\sqrt{3}}{4}=[/tex]
[tex]=\dfrac{\frac{400\sqrt{3}}{3}}{4}=\frac{400\sqrt{3}}{3}:4=\frac{\not400^1^0^0\sqrt{3}}{3}\cdot\frac{1}{\not4_{1}}=\frac{100\sqrt{3}}{3}[/tex]
