For this case we have that by definition, the domain of a function is given by all the values of "x" for which the function is defined.
In this case we have:
[tex]R {(6, -2), (1, 2), (-3,-4), (-3, 2)}[/tex]
Thus, it is observed that the values of "x" of the relation R are given by:
[tex]x: 6,1, -3[/tex]
Therefore, the domain is: {-3,1,6}
ANswer:
Option D