[tex] \bf ~~~~~~~~~~~~\textit{distance between 2 points}
\\\\
(\stackrel{x_1}{2}~,~\stackrel{y_1}{1})\qquad
(\stackrel{x_2}{14}~,~\stackrel{y_2}{6})\qquad \qquad
d = \sqrt{( x_2- x_1)^2 + ( y_2- y_1)^2}
\\\\\\
d=\sqrt{(14-2)^2+(6-1)^2}\implies d=\sqrt{12^2+5^2}
\\\\\\
d=\sqrt{144+25}\implies d=\sqrt{169}\implies d=13 [/tex]
