This 2nd rule is not entirely dissimilar from the 1st, and states that the square root of a fraction equates to the same value as the square root of the numerator divide by the square root of the denominator. Once again a small example or two should help to cement this into place:

Once again I have decided to use to numbers where the square roots are quite obvious, the square root of 49 being 7 and the square root of 64 being 8 so the answer to the above expression will be the fraction 7/8.