Which function rule models the function over the domain specified in the table below?

[tex]\[
\begin{tabular}{|c|c|}
\hline
$x$ & $f(x)$ \\
\hline
-7 & -11 \\
\hline
-1 & 1 \\
\hline
3 & 9 \\
\hline
4 & 11 \\
\hline
7 & 17 \\
\hline
\end{tabular}
\][/tex]

A. [tex]$f(x) = 3x + 10$[/tex]
B. [tex]$f(x) = 2x + 3$[/tex]
C. [tex]$f(x) = 4x + 5$[/tex]
D. [tex]$f(x) = 3x - 10$[/tex]



Answer :

Let's determine the correct function rule that matches the given (x, f(x)) pairs. Given the table:

[tex]\[ \begin{array}{|c|c|} \hline x & f(x) \\ \hline -7 & -11 \\ \hline -1 & 1 \\ \hline 3 & 9 \\ \hline 4 & 11 \\ \hline 7 & 17 \\ \hline \end{array} \][/tex]

We need to check each proposed function rule to see which one correctly calculates [tex]\(f(x)\)[/tex] for all given x values.

### Checking [tex]\(f(x) = 3x + 10\)[/tex]
- When [tex]\(x = -7\)[/tex]:
[tex]\[ f(-7) = 3(-7) + 10 = -21 + 10 = -11 \][/tex]
Matches the table value.

- When [tex]\(x = -1\)[/tex]:
[tex]\[ f(-1) = 3(-1) + 10 = -3 + 10 = 7 \][/tex]
Does not match the table value (table value is 1).

Since there is no match for [tex]\(x = -1\)[/tex], [tex]\(f(x) = 3x + 10\)[/tex] is not the correct function rule.

### Checking [tex]\(f(x) = 2x + 3\)[/tex]
- When [tex]\(x = -7\)[/tex]:
[tex]\[ f(-7) = 2(-7) + 3 = -14 + 3 = -11 \][/tex]
Matches the table value.

- When [tex]\(x = -1\)[/tex]:
[tex]\[ f(-1) = 2(-1) + 3 = -2 + 3 = 1 \][/tex]
Matches the table value.

- When [tex]\(x = 3\)[/tex]:
[tex]\[ f(3) = 2(3) + 3 = 6 + 3 = 9 \][/tex]
Matches the table value.

- When [tex]\(x = 4\)[/tex]:
[tex]\[ f(4) = 2(4) + 3 = 8 + 3 = 11 \][/tex]
Matches the table value.

- When [tex]\(x = 7\)[/tex]:
[tex]\[ f(7) = 2(7) + 3 = 14 + 3 = 17 \][/tex]
Matches the table value.

Since all values match the table, [tex]\(f(x) = 2x + 3\)[/tex] is the correct function rule.

### Checking [tex]\(f(x) = 4x + 5\)[/tex]
- When [tex]\(x = -7\)[/tex]:
[tex]\[ f(-7) = 4(-7) + 5 = -28 + 5 = -23 \][/tex]
Does not match the table value (table value is -11).

Since there is no match for [tex]\(x = -7\)[/tex], [tex]\(f(x) = 4x + 5\)[/tex] is not the correct function rule.

### Checking [tex]\(f(x) = 3x - 10\)[/tex]
- When [tex]\(x = -7\)[/tex]:
[tex]\[ f(-7) = 3(-7) - 10 = -21 - 10 = -31 \][/tex]
Does not match the table value (table value is -11).

Since there is no match for [tex]\(x = -7\)[/tex], [tex]\(f(x) = 3x - 10\)[/tex] is not the correct function rule.

After checking all the function rules, we determine that the correct function that models the data given in the table is:

[tex]\[ f(x) = 2x + 3 \][/tex]