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)
Where (color(blue)(x_1), color(blue)(y_1), color(blue)(z_1)) and (color(red)(x_1), color(red)(y_1), color(red)(z_1)) are two points.
Substituting the values from the points in the problem gives:
d = sqrt((color(red)(-3) - color(blue)(13))^2 + (color(red)(-37) - color(blue)(-23))^2 + (color(red)(-22) - color(blue)(-20))^2)
d = sqrt((color(red)(-3) - color(blue)(13))^2 + (color(red)(-37) + color(blue)(23))^2 + (color(red)(-22) + color(blue)(20))^2)
d = sqrt((-16)^2 + (-14)^2 + (-2)^2)
d = sqrt(256 + 196 + 4)
d = sqrt(456)
d = sqrt(4 * 114)
d = sqrt(4)sqrt(114)
d = 2sqrt(114)
Or, approximately:
d ~= 21.354