Try this explanation/solution:
1st way, based on the attached graph (approximated values): the best solution is the intersection point of those two lines. Coordinates are (-6.5;-3.5).
2d way, based on principles of algebra (exact values): the best solution is from the system of two equations:
[tex] \left \{ {{3x-2y=-12} \atop {x-4y=8}} \right. \ =\ \textgreater \ \ \left \{ {{y=-3.6} \atop {x=-6.4}} \right. [/tex]
Answer: D (or 4th).
