Final answer:
To determine an appropriate viewing rectangle for a relation, consider the range of values in the relation's domain and range.
Step-by-step explanation:
To determine an appropriate viewing rectangle for a relation, you need to consider the range of values in the relation's domain and range. In this case, the relation {(3,2),(-9,5),(-4,-2),(2,-6)} has a domain of {-9, 2, 3} and a range of {-6, -2, 2, 5}. So, an appropriate viewing rectangle would be D. [-10,10,1] by [-4,4,1], because it includes all the values in the domain and range of the relation.