[tex]zad.7)\\\\przekatna\ kwadratu:\ \ d=5\\\\d=a\sqrt{2}\\\\a\sqrt{2}=5\ \ |:\sqrt{2}\\\\a=\frac{5}{\sqrt{2}}*\frac{\sqrt{2}}{\sqrt{2}}=\frac{5\sqrt{2}}{2}\\\\obwod\ kwadratu:\\\\O=4a\\\\O=\not{4}^2*\frac{5\sqrt{2}}{\not{2}^1}=10\sqrt{2}\\\\odp.\ B.[/tex]
