Points and their residual values are shown in the table.

[tex]\[
\begin{tabular}{|c|c|c|}
\hline
$x$ & $y$ & Residual \\
\hline
1 & 3.3 & 0.68 \\
\hline
2 & 5 & 0.04 \\
\hline
3 & 6.2 & -1.1 \\
\hline
4 & 9 & -0.64 \\
\hline
5 & 13 & 1.02 \\
\hline
\end{tabular}
\][/tex]

Which point is farthest from the line of best fit?

A. [tex]$(1, 3.3)$[/tex]

B. [tex]$(2, 5)$[/tex]

C. [tex]$(3, 6.2)$[/tex]

D. [tex]$(4, 9)$[/tex]

E. [tex]$(5, 13)$[/tex]



Answer :

To determine which point is farthest from the line of best fit, we need to look at the residuals. The residual for a data point is the difference between the observed value and the value predicted by the line of best fit.

We'll follow these steps:

1. Residuals from the table:
[tex]\[ \begin{array}{|c|c|c|} \hline x & y & \text{Residual} \\ \hline 1 & 3.3 & 0.68 \\ \hline 2 & 5 & 0.04 \\ \hline 3 & 6.2 & -1.1 \\ \hline 4 & 9 & -0.64 \\ \hline 5 & 13 & 1.02 \\ \hline \end{array} \][/tex]

2. Absolute residuals:
To find the point farthest from the line, we consider the magnitude (absolute value) of the residuals:
- For [tex]\(x = 1\)[/tex], the residual is [tex]\( \left|0.68\right| = 0.68 \)[/tex]
- For [tex]\(x = 2\)[/tex], the residual is [tex]\( \left|0.04\right| = 0.04 \)[/tex]
- For [tex]\(x = 3\)[/tex], the residual is [tex]\( \left|1.1\right| = 1.1 \)[/tex]
- For [tex]\(x = 4\)[/tex], the residual is [tex]\( \left|0.64\right| = 0.64 \)[/tex]
- For [tex]\(x = 5\)[/tex], the residual is [tex]\( \left|1.02\right| = 1.02 \)[/tex]

3. Compare the absolute residuals:
Now, we compare the absolute residuals to find the maximum value:
- [tex]\( 0.68 \)[/tex]
- [tex]\( 0.04 \)[/tex]
- [tex]\( 1.1 \)[/tex]
- [tex]\( 0.64 \)[/tex]
- [tex]\( 1.02 \)[/tex]

The maximum absolute residual is [tex]\( 1.1 \)[/tex].

4. Identify the corresponding point:
The point with the residual of [tex]\( -1.1 \)[/tex] corresponds to [tex]\( x = 3 \)[/tex] and [tex]\( y = 6.2 \)[/tex].

Thus, the point [tex]\((3, 6.2)\)[/tex] is farthest from the line of best fit with a residual value of [tex]\(-1.1\)[/tex].