In general, the formula to calculate the distance between two points on the plane is
[tex]\begin{gathered} (x_1,y_1),(x_2,y_2) \\ \Rightarrow distance=\sqrt{(x_1-x_2)^2+(y_1-y_2)^2} \end{gathered}[/tex]Therefore, in our case,
[tex]\begin{gathered} (16,-3),(2,-5) \\ \Rightarrow distance=\sqrt{(16-2)^2+(-3+5)^2}=\sqrt{14^2+2^2}=\sqrt{200}=10\sqrt{2}\approx14.142135... \end{gathered}[/tex]