If you want to ace the exam, your PDF notes should definitely cover these heavy-hitters: Topic Area Key Concepts to Note
For a system $AX = B$ where $A$ is $n \times n$ and $\det A \neq 0$: $$x_i = \frac\det A_i\det A$$ ($A_i$ is matrix $A$ with the $i$-th column replaced by $B$). dse m2 notes pdf
If you want to ace the exam, your PDF notes should definitely cover these heavy-hitters: Topic Area Key Concepts to Note
For a system $AX = B$ where $A$ is $n \times n$ and $\det A \neq 0$: $$x_i = \frac\det A_i\det A$$ ($A_i$ is matrix $A$ with the $i$-th column replaced by $B$).
