We consider the system $$\begin{pmatrix}-5 & 2 & 0.5\\ 0 & -20 & 1 \\ 4 & -1 & 4\end{pmatrix}\vec{x}=\begin{pmatrix}4 \\ -30\\ 42\end{pmatrix}$$ I have applied the Jacobi method with 3 iterations.
Then I applied the method with the inverse matrix and the Cramer's Rule. At these both methods I don't get the exact same result but approximately the same. Which method of these two is better? With which do we get a better result?