Odpowiedź:
[tex]|AC| =\sqrt{(1-1)^{2} +(1+4)^{2} } =\sqrt{5^{2} } =5\\|BC|=\sqrt{(5-1)^{2} +(4-1)^{2} } =\sqrt{16+3} =\sqrt{19} \\Obwod:=5+5+\sqrt{19} +\sqrt{19} = 10+2\sqrt{19}[/tex]
