Jenna constructs the model to represent 3x2 11x – 4. what factors does jenna need to model for the sides?

The choices are the below that can be elsewhere:

(3x + 1) and (x – 4)
(3x – 1) and (x + 4)
(3x – 2) and (x + 2)
(3x + 2) and (x – 2)

I assume that the correct equation is  3x2 + 11x – 4. The answer is (3x – 1) and (x + 4). 

In all honesty, there really is no “work” per say to show. mainly it’s just using the process of elimination. the question is asking which domain(s) would be the most appropriate for the function c(n). n is the number of observed vehicles so right away, 1, 2, and 3 can be eliminated.why? 1, 2 start in the negatives and therefore it is impossible to observe negative cars. so, #4 would be the best answer to the given problem.