Which set of ordered pairs does not represent a function?

Question

Answer
Multiple Choice Answers
left curly bracket, left bracket, minus, 6, comma, minus, 4, right bracket, comma, left bracket, minus, 2, comma, minus, 4, right bracket, comma, left bracket, minus, 4, comma, minus, 7, right bracket, comma, left bracket, 7, comma, minus, 6, right bracket, right curly bracket{(−6,−4),(−2,−4),(−4,−7),(7,−6)}
left curly bracket, left bracket, 1, comma, minus, 9, right bracket, comma, left bracket, 5, comma, 2, right bracket, comma, left bracket, minus, 9, comma, 4, right bracket, comma, left bracket, 5, comma, minus, 5, right bracket, right curly bracket{(1,−9),(5,2),(−9,4),(5,−5)}
left curly bracket, left bracket, minus, 1, comma, 9, right bracket, comma, left bracket, minus, 9, comma, 3, right bracket, comma, left bracket, minus, 8, comma, 9, right bracket, comma, left bracket, minus, 7, comma, minus, 2, right bracket, right curly bracket{(−1,9),(−9,3),(−8,9),(−7,−2)}
left curly bracket, left bracket, 9, comma, minus, 3, right bracket, comma, left bracket, 8, comma, 0, right bracket, comma, left bracket, minus, 5, comma, minus, 3, right bracket, comma, left bracket, 1, comma, 2, right bracket, right curly bracket{(9,−3),(8,0),(−5,−3),(1,2)}

Answer 1

The set of ordered pairs that does not represent a function is {(1,−9),(5,2),(−9,4),(5,−5)}.