[tex]Zadanie\ 1\\\\a=18\ cm\\\\h=\frac{a\sqrt{3} }{2}\\\\h=\frac{18\sqrt{3} }{2}=9\sqrt{3}\ cm\\\\\\Zadanie\ 2\\\\h=9\ dm\\\\ h=\frac{a\sqrt{3} }{2}\\\\\frac{a\sqrt{3} }{2}=9\ \ \mid \cdot2\\\\a\sqrt{3}=18\ \ \mid\cdot\sqrt{3}\\\\3a=18\sqrt{3}\ \ \mid:3\\\\a= 6\sqrt{3}\ dm\\\\\\Zadanie\ 3\\\\a=4\ cm\\\\P=\frac{a^2\sqrt{3} }{4}\\\\P= \frac{4^2\cdot\sqrt{3} }{4}=\frac{16\sqrt{3} }{4}=4\sqrt{3}\ cm^2[/tex]
[tex]Zadanie\ 4\\\\ Ob.=18\ m\\\\Ob.=3\cdot a\\\\3\cdot a=18\ \ \mid:3\\\\a=6\ m\\\\P= \frac{a^2\sqrt{3} }{4}\\\\P= \frac{6^2\cdot\sqrt{3} }{4}=\frac{36\sqrt{3} }{4}= 9\sqrt{3}\ m^2\\\\\\Zadanie\ 5\\\\h=6\ m\\\\h=\frac{a\sqrt{3} }{2}\\\\\frac{a\sqrt{3} }{2}=6\ \ \mid\cdot2\\\\a\sqrt{3}=12\ \ \mid\cdot\sqrt{3}\\\\3a=12\sqrt{3}\ \ \mid:3 \\\\a=4\sqrt{3}\ m\\\\P=\frac{1}{2}\cdot a\cdot h\\\\P=\frac{1}{2}\cdot4\sqrt{3}\cdot 6=12\sqrt{3}\ m^2[/tex]
