Final answer:
The domain of the given relation is {7, 3, 5, -5}, which consists of all the first components of the ordered pairs in the relation.
Step-by-step explanation:
The domain of a relation in mathematics refers to the set of all possible x-values which can be input into the function. Considering the provided relation {(7,8),(3,-10),(5,0),(-5,4)}, the numbers in the domain are those that appear as the first component in each ordered pair. Therefore, the domain of this relation is {7, 3, 5, -5}. It is important to recognize that the domain represents the input values and these are the x-coordinates in a Cartesian coordinate system.