Question

nu știu acest exercițiu am nevoie de ajutor...​

Answer 1

$a)\:\: AB=\sqrt{(x_A-x_B)^2+(y_A-y_B)^2}\\ AB=\sqrt{(3-5)^2+(3-7)^2}\\ AB=\sqrt{(-2)^2+(-4)^2}\\ AB=\sqrt{4+16}=\sqrt{20}=2\sqrt{5}\\\sout{-------------------}\\ BC=\sqrt{(x_B-x_C)^2+(y_B-y_C)^2}\\ BC=\sqrt{(5+3)^2+(7-5)^2}\\ BC=\sqrt{8^2+2^2}\\ BC=\sqrt{64+4}=\sqrt{68}=2\sqrt{17}\\\sout{-------------------}\\ AC=\sqrt{(x_A-x_C)^2+(y_A-y_C)^2}\\ AC=\sqrt{(3+3)^2+(3-5)^2}\\ AC=\sqrt{6^2+(-2)^2}\\ AC=\sqrt{36+4}=\sqrt{40}=2\sqrt{10}\\\\\\\\ b) \:\: P_{ΔABC}=AB+BC+AC\\ P_{ΔABC}=2\sqrt{5}+2\sqrt{17}+2\sqrt{10}\\ P_{ΔABC}=2(\sqrt{5}+\sqrt{17}+\sqrt{10}$