What do we call a relation where each value of x is paired with a unique value of y?

What do we call a relation where each value of x is paired with a unique value of y?

• A. Relation
• B. Mapping
• C. Graph
• D. Function

Answer: (D)

The concept being tested is what defines a function: every input value x has exactly one output value y. This one-output rule means that for any given x, you can predict a single y. If an x could be paired with more than one y, that isn’t a function. A relation can be any pairing of x and y, and a graph is just a visual representation of those pairs, but the precise term for this single-output behavior is a function. For example, if x = 3, the function assigns one specific y, say y = 7; if an x had two different y’s, that would not be a function.

The concept being tested is what defines a function: every input value x has exactly one output value y. This one-output rule means that for any given x, you can predict a single y. If an x could be paired with more than one y, that isn’t a function. A relation can be any pairing of x and y, and a graph is just a visual representation of those pairs, but the precise term for this single-output behavior is a function. For example, if x = 3, the function assigns one specific y, say y = 7; if an x had two different y’s, that would not be a function.