Answer
SSS and SAS
Work Step by Step
The Law of Cosines states that $c^2=a^2+b^2-2ab\cdot cos\theta$, which means that it can be used to solve problems knowing SAS (side-angle-side) and SSS (side-side-side), however, this law can not be used for
ASA (angle-side-angle) and SSA (side-side-angle) where the Law of Sines should be used.
Thus, the answers to this question are SSS and SAS.
