This problem is actually simple because it is a 30-60-90 triangle.
Because we know that \(CD = 8\sqrt3\), \(AD\) must equal \(\sqrt2\times 8\sqrt3 = 8\sqrt6\)
We also know that \(BD\) must equal to \({8\sqrt3}\over\sqrt2\), which can be rewritten as \(4\sqrt6\).
This means that \(\color{brown}\boxed{AB=12\sqrt6}\)
Note that triangles ACD , CBD are similar and each are 30-60-90 right triangles
And since AD is opposite a 60° angle it = sqrt 3 * CD = sqrt 3 * 8 sqrt 3 = 24
And, by similar triangles, we have the following relationship
DB / DC = DC / AD
DC^2 = DB * AD
(8sqrt 3)^2 = DB * 24
256 / 24 = DB = 32 / 3 (cm)
I misread the question... DB should be \(4 \sqrt6\), because \(\triangle{CDB}\) is a 30-60-90.