Final answer:
The best equation that matches the situation described in the question is y = -2000x + 26000.
Step-by-step explanation:
The best equation that matches the situation described in the question is y = -2000x + 26000. This equation represents a linear relationship, where the value of the van decreases over time at a constant rate. The initial value of the van is $26,000, and it decreases by $2,000 every year.