Which of the following represents a function?

A.
[tex]\[
\begin{tabular}{|c|c|c|c|c|}
\hline
$x$ & -10 & -9 & 0 & 5 \\
\hline
$y$ & 19 & 17 & 25 & 19 \\
\hline
\end{tabular}
\][/tex]

B. [tex]\[((0,0),(-4,3),(7,1),(-4,5),(3,2))\][/tex]



Answer :

To determine whether each given relation represents a function, we need to check if every input value (x-coordinate) maps to exactly one output value (y-coordinate).

### Relation 1 — Represented by the table:
[tex]\[ \begin{array}{|c|c|c|c|c|} \hline x & -10 & -9 & 0 & 5 \\ \hline y & 19 & 17 & 25 & 19 \\ \hline \end{array} \][/tex]

In this table:
- [tex]\( x = -10 \)[/tex] maps to [tex]\( y = 19 \)[/tex]
- [tex]\( x = -9 \)[/tex] maps to [tex]\( y = 17 \)[/tex]
- [tex]\( x = 0 \)[/tex] maps to [tex]\( y = 25 \)[/tex]
- [tex]\( x = 5 \)[/tex] maps to [tex]\( y = 19 \)[/tex]

We observe that each input [tex]\( x \)[/tex] value is unique and maps to exactly one [tex]\( y \)[/tex] value. Therefore, this relation does represent a function.

### Relation 2 — Represented by the list of tuples:
[tex]\[ ((0,0),(-4,3),(7,1),(-4,5),(3,2)) \][/tex]

Here, we have the set of pairs:
- [tex]\((0, 0)\)[/tex]
- [tex]\((-4, 3)\)[/tex]
- [tex]\((7, 1)\)[/tex]
- [tex]\((-4, 5)\)[/tex]
- [tex]\((3, 2)\)[/tex]

We need to check each input [tex]\( x \)[/tex] value:
- [tex]\(0\)[/tex] maps to [tex]\(0\)[/tex]
- [tex]\(-4\)[/tex] maps to [tex]\(3\)[/tex] and [tex]\(-4\)[/tex] also maps to [tex]\(5\)[/tex]

The input value [tex]\(-4\)[/tex] maps to two different outputs ([tex]\(3\)[/tex] and [tex]\(5\)[/tex]). This means that for the same input [tex]\(x = -4\)[/tex], there are multiple outputs.

Hence, this relation does not represent a function because a single input maps to more than one output.

### Conclusion:
- The table [tex]\[ \begin{array}{|c|c|c|c|c|} \hline x & -10 & -9 & 0 & 5 \\ \hline y & 19 & 17 & 25 & 19 \\ \hline \end{array} \][/tex] represents a function.

- The list of tuples [tex]\(((0, 0), (-4, 3), (7, 1), (-4, 5), (3, 2))\)[/tex] does not represent a function.

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