Final answer:
Using a linear equation in place of a quadratic equation is more problematic in the long-term due to increased divergence between the two over time, leading to erroneous predictions and decisions.
Step-by-step explanation:
Using a linear equation instead of a quadratic equation would generally be more problematic in the long-term, because while a linear model might approximate a quadratic trend adequately over a short-term range, deviations between the two will grow increasingly significant over the long-term. For instance, if you were using the equations to predict the trajectory of a projectile, the linear model might initially seem to adequately represent the path, however, as time goes on, the actual trajectory, which more closely resembles a parabola, would diverge significantly from the straight path predicted by a linear model.
The issue arises because linear equations represent constant change, whereas quadratic equations represent situations where the rate of change is also changing (accelerating or decelerating). Thus, for predictions or analysis over an extended period, the shortcomings of the linear model would become far more evident and impactful, potentially leading to erroneous predictions and decisions based on such models.