[tex]~~~~~~~~~~~~\textit{distance between 2 points} \\\\ A(\stackrel{x_1}{-7}~,~\stackrel{y_1}{5})\qquad B(\stackrel{x_2}{4}~,~\stackrel{y_2}{-9})\qquad \qquad d = \sqrt{( x_2- x_1)^2 + ( y_2- y_1)^2} \\\\\\ AB=\sqrt{[4 - (-7)]^2 + [-9 - 5]^2}\implies AB=\sqrt{(4+7)^2+(-14)^2} \\\\\\ AB=\sqrt{121+196}\implies AB=\sqrt{317}[/tex]