Question 121524
The distance between two points is given by,
{{{D^2=(x[1]-x[2])^2+(y[1]-y[2])^2)}}}
{{{D^2=(9-9)^2+(-4-1)^2)}}}
{{{D^2=(0)+(-5)^2)}}}
{{{D^2=25)}}}
{{{D=5}}}