Which is a function
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Answer:
Function, in mathematics, an expression, rule, or law that defines a relationship between one variable (the independent variable) and another variable (the dependent variable). Functions are ubiquitous in mathematics and are essential for formulating physical relationships in the sciences.
Step-by-step explanation:
Step-by-step explanation:
the second group. a function cannot have 2 of the same x values.
(7,9)
(20,14)
(9,-12)
(0,-9)