The formula for calculating the distance between two points is:
#d = sqrt((color(red)(x_2) - color(blue)(x_1))^2 + (color(red)(y_2) - color(blue)(y_1))^2 + (color(red)(z_2) - color(blue)(z_1))^2)#
Substituting the values from the points in the problem gives:
#d = sqrt((color(red)(-1) - color(blue)(-13))^2 + (color(red)(-6) - color(blue)(13))^2 + (color(red)(-2) - color(blue)(-4))^2)#
#d = sqrt((color(red)(-1) + color(blue)(13))^2 + (color(red)(-6) - color(blue)(13))^2 + (color(red)(-2) + color(blue)(4))^2)#
#d = sqrt(12^2 + (-19)^2 + 2^2)#
#d = sqrt(144 + 361 + 4)#
#d = sqrt(509)#
Or
#d = 22.561# rounded to the nearest thousandth