[tex]Zadanie\\\\a=5\\c=a+2=5+2=7\\b=?\\\\a^2+b^2=c^2\\\\ 5^2+b^2=7^2\\\\25+b^2= 49\ \ \mid-25\\\\b^2=24\\\\b=\sqrt{24}=\sqrt{4\cdot6}\\\\b=2\sqrt{6}\\\\\\P=\frac{1}{2}\cdot a\cdot b\\\\P=\frac{1}{2}\cdot5\cdot2\sqrt{6}=5\sqrt{6}\ (j^2)\\\\\\ Ob.=a+b+c\\\\Ob.=5+2\sqrt{6}+7=12+2\sqrt{6}=2(6+\sqrt{6})\ (j)[/tex]