Calculate the distance between two points.

Using the distance formula, $d = \sqrt{(x_2-x_1)^2 + (y_2-y_1)^2}$, we plug in the coordinates of A and B: $d = \sqrt{(11 - (-1))^2 + (-8 - (-3))^2} = \sqrt{(12)^2 + (-5)^2} = \sqrt{144 + 25} = \sqrt{169} = 13$.