Let \( S_1 \) and \( S_2 \) be respectively the sets of all \( a \in R - \{0\} \) for which the system of linear equations.
\( ax + 2ay - 3az = 1 \)
\( (2a + 1)x + (2a + 3)y + (a + 1)z = 2 \)
\( (3a + 5)x + (a + 5)y + (a + 2)z = 3 \)
has unique solution and infinitely many solutions. Then: