In a cube, an edge = a side, and since all edges and sides are equivalent in a cube, then the lateral surface area (SA) pertains to a square side of the cube.
So, take the square root (sr) of the lateral SA to get one side (s), then cube it to get the volume of the cube. But since the problem just asks for the length of one edge, then:
sr (SA) = side or edge
sr144 = 12