Decide whether a relation is a function

Question 1

Is this relation a function? (6, −5), (−5, 9), (0, 5), (6, −6)

• A. Yes
• B. No

Question 2

Is this rule a function (one output for every input)? Side length of a square → its area

• A. Yes
• B. No

Question 3

Is this relation a function? (−2, −5), (2, −2), (2, −3), (7, 6)

• A. Yes
• B. No

Question 4

Is this rule a function (one output for every input)? Each date of birth → the students born that day

• A. Yes
• B. No

Question 5

Is this relation a function? (4, 6), (1, −8), (−5, 2), (8, 9)

• A. Yes
• B. No

Question 6

Is this rule a function (one output for every input)? Each student → their date of birth

• A. Yes
• B. No

Question 7

Is this relation a function? (2, −6), (2, −7), (6, 6), (7, −8)

• A. Yes
• B. No

Question 8

Is this rule a function (one output for every input)? Side length of a square → its area

• A. Yes
• B. No

Question 9

Is this relation a function? (1, 7), (7, 5), (0, −9), (9, 1)

• A. Yes
• B. No

Question 10

Is this rule a function (one output for every input)? A shop's opening hour → the number of customers at that time on different days

• A. Yes
• B. No

Question 11

Is this relation a function? (−4, 0), (8, 3), (3, 2), (3, 4)

• A. Yes
• B. No

Question 12

Is this rule a function (one output for every input)? Each student → their date of birth

• A. Yes
• B. No

Question 13

Is this relation a function? (5, 7), (1, 2), (−5, −7), (−5, −9)

• A. Yes
• B. No

Question 14

Is this rule a function (one output for every input)? A shop's opening hour → the number of customers at that time on different days

• A. Yes
• B. No

Question 15

Is this relation a function? (3, −5), (0, −2), (−5, −1), (−3, −5)

• A. Yes
• B. No

Question 16

Is this rule a function (one output for every input)? Each date of birth → the students born that day

• A. Yes
• B. No