Which set of ordered pairs represents a function? \{(-4, 9), (-5, 4), (-5, -2), (1, -6)\}{(−4,9),(−5,4),(−5,−2),(1,−6)}
\{(2, 6), (5, 1), (9, 4), (2, -6)\}{(2,6),(5,1),(9,4),(2,−6)}
\{(-7, -8), (0, 1), (-3, 9), (-4, -8)\}{(−7,−8),(0,1),(−3,9),(−4,−8)}
\{(-6, -5), (-3, -4), (6, 6), (-3, 8)\}{(−6,−5),(−3,−4),(6,6),(−3,8)}