Answer:
1,200 - 0.97x = population/year
Step-by-step explanation:
Decreasing at an average rate of 3% per year is also the same as saying 0.97 * a year. Since x represents years, this can be 0.97 * x, or just 0.97x. Now, since the beginning population was 1,200 and the population is decreasing, just subtract the new population per year by the original population, and equation equal to this is: 1,200 - 0.97x = population/year