0 ≤ a ≤ 5 would be an accurate constraint on "a" in the context.
Let's assume "a" represents the number of adults and "c" represents the number of children. Since there are a total of 5 people on the elevator, we can represent this with the following equation:
a + c = 5
Additionally, we know that the total weight of 5 people is 570 pounds. Since an adult weighs 180 pounds and a child weighs 70 pounds, we can represent this with the following equation:
180a + 70c = 570
This system of equations accurately represents the given situation.
As for an accurate constraint on "a", we know that there cannot be a negative number of adults on the elevator. Therefore, "a" must be a non-negative integer.
Additionally, since there are a total of 5 people, we know that "a" cannot be greater than 5. Therefore, 0 ≤ a ≤ 5 would be an accurate constraint on "a" in the context.