The formula fro the volume of a pyramid with a square base is:
Volume = L * L * H / 3
L * L * 9.6 / 3 = 147.97
L * L = (3 * 147.97) / 9.6
L * L = 46.24
Let's take the square root of both sides.
L = sqrt(46.24) = 6.8
The length of one edge of the square base is 6.8 units.