Answer:
B
Step-by-step explanation:
that is the definition of a function : every valid value of x gets exactly one value of y assigned as function result value.
that allows gaps. not every value on the x-axis has to be a valid x value for the function. and neither do we need every possible y value to be a valid function result value.
so, if we consider x to be the set of {2, 4, 6, 9}, then this is indeed a function.
2 gets 3, 4 gets 9, 6 gets 10, and 9 gets 5 assigned as y (function result) value.
all good and perfect - exactly one assigned value for every valid x value.
