A mapping diagram showing a relation, using arrows, between input and output for the following ordered pairs: (negative 3, negative 9), (2, negative 6), (negative 5, 4), (1, 2), (6, 0). What is the domain of the function shown in the mapping? {x | x = –5, –3, 1, 2, 6} {y | y = –9, –6, 0, 2, 4} {x | x = –9, –6, –5, –3, 0, 1, 2, 4, 6} {y | y = –9, –6, –5, –3, 0, 1, 2, 4, 6}