Which matrix represents the system of equations shown?

Answer:
b.
by relation
[tex] \binom{3x \: \: - 2y \: \: 12}{4x \: \: \: \: - y \: \: \: \: \: 9} \\ eliminate \: the \: unknowns \: (x \: and \: y) \\ \binom{3 \: \: - 2 \: \: 12}{4 \: \: \: \: - 1 \: \: \: \: \: 9} [/tex]