In quadilateral $ABCD$ (usual clockwise or anticlockwise naming), $AB=16\sqrt{2}$ cm, $CD=10$ cm, $DA=8.5$ cm, $\angle D = 120^\circ $ and $\angle ACB = 45^\circ$. How to find $\angle ABC$?
ADDED:
As stated in one of the answer, the obvious approach, utilizing the law of cosines and sines gives a very ugly form for a problem that is intended for pencil-paper calculation. I was wondering if there is any alternative approach to avoid doing the messy parts?