Question

Which choice shows a function with a domain of {–4, –2, 2, 4}?
On a coordinate plane, a vertical line is at x = 2.
On a coordinate plane, a line goes through (negative 2, negative 2) and (0, negative 3).
{(–4, 2), ( –2, 1), (2, 0), (4, 5)}
{(1, –4), (0, –2), (2, 2), (6, 4)}

Answer 1

{(–4, 2), (–2, 1), (2, 0), (4, 5)}

Reason: the domain of a relation is the set of x-values. This set has x-values {–4, –2, 2, 4}. The vertical line x = 2 has domain {2}, the line through (–2,–2) and (0,–3) has infinitely many x-values, and the last set has domain {1,0,2,6}.