[tex]Zadanie\ 1\\\\a=2\sqrt{5}\\c=5\\\\a^2+b^2=c^2\\\\(2\sqrt{5})^2+b^2=5^2\\\\ 20+b^2=25 \ \ \mid-20\\\\b^2=5\\\\b=\sqrt{5}\\\\\\ Zadanie\ 2\\\\A=(2,-3)\ ;\ B=(-3,1)\\\\\mid AB\mid=\sqrt{(x_B-x_A)^2+(y_B-y_A)^2}\\\\\mid AB\mid=\sqrt{(-3-2)^2+[1-(-3)]^2}= \sqrt{(-5)^2+4^2}=\sqrt{25+16}=\sqrt{41}\\\\\mid AB\mid=a= \sqrt{41}\ (j)\\\\P=a^2\\\\P=(\sqrt{41})^2=41\ (j^2)[/tex]