[tex]\bf ~~~~~~~~~~~~\textit{distance between 2 points} \\\\ (\stackrel{x_1}{-7}~,~\stackrel{y_1}{4})\qquad (\stackrel{x_2}{5}~,~\stackrel{y_2}{-7})\qquad \qquad d = \sqrt{( x_2- x_1)^2 + ( y_2- y_1)^2} \\\\\\ d = \sqrt{[5-(-7)]^2+[-7-4]^2}\implies d=\sqrt{(5+7)^2+(-7-4)^2} \\\\\\ d=\sqrt{12^2+(-11)^2}\implies d = \sqrt{144+121}\implies d = \sqrt{265}\implies d\approx 16.28[/tex]