Select the correct answer.

Annabeth and Charlie are both on road trips. Annabeth's distance, in miles, from New York [tex]\( t \)[/tex] hours after 12:00 p.m. is modeled by this function:

[tex]\[
D(t)=60|t-3|
\][/tex]

Charlie's distance, in miles, from New York [tex]\( t \)[/tex] hours after 12:00 p.m. is modeled by this table:

[tex]\[
\begin{tabular}{|c|c|c|c|c|c|c|}
\hline
$t$ & 0 & 2 & 4 & 6 & 8 & 10 \\
\hline
$F(t)$ & 270 & 180 & 90 & 0 & 90 & 180 \\
\hline
\end{tabular}
\][/tex]

Who will have traveled for a greater amount of time when their distance from New York stops decreasing and starts increasing?

A. Charlie
B. Annabeth
C. This cannot be determined from the given information
D. They will have traveled the same amount of time.



Answer :

Let's break down and analyze the given information to answer the question, "Who will have traveled for a greater amount of time when their distance from New York stops decreasing and starts increasing?"

Annabeth's Distance Model:
Annabeth's distance, [tex]\( D(t) \)[/tex], from New York is given by the function:
[tex]\[ D(t) = 60 \times |t - 3| \][/tex]

To understand when Annabeth's distance stops decreasing and starts increasing, we need to analyze the absolute value function. The critical point for the absolute value function [tex]\( |t - 3| \)[/tex] occurs at [tex]\( t = 3 \)[/tex]. This is where the function changes behavior.

Summary for Annabeth:
- Up to [tex]\( t = 3 \)[/tex]: Annabeth's distance decreases.
- After [tex]\( t = 3 \)[/tex]: Annabeth's distance increases.
- Therefore, Annabeth's distance from New York stops decreasing and starts increasing at [tex]\( t = 3 \)[/tex] hours.

Charlie's Distance Model:
Charlie's distance, [tex]\( F(t) \)[/tex], from New York is represented by the table:

[tex]\[ \begin{array}{|c|c|c|c|c|c|c|} \hline t & 0 & 2 & 4 & 6 & 8 & 10 \\ \hline F(t) & 270 & 180 & 90 & 0 & 90 & 180 \\ \hline \end{array} \][/tex]

From the table, we can observe how Charlie's distance changes over time:
- From [tex]\( t = 0 \)[/tex] to [tex]\( t = 6 \)[/tex]: Charlie's distance decreases from 270 miles to 0 miles.
- From [tex]\( t = 6 \)[/tex] to [tex]\( t = 10 \)[/tex]: Charlie's distance starts increasing again from 0 miles to 180 miles.

Summary for Charlie:
- Up to [tex]\( t = 6 \)[/tex]: Charlie's distance decreases.
- After [tex]\( t = 6 \)[/tex]: Charlie's distance increases.
- Therefore, Charlie's distance from New York stops decreasing and starts increasing at [tex]\( t = 6 \)[/tex] hours.

Comparison:
Now, we need to compare who traveled for a greater amount of time when their distance stopped decreasing and started increasing:

- Annabeth's critical time: [tex]\( t = 3 \)[/tex] hours
- Charlie's critical time: [tex]\( t = 6 \)[/tex] hours

Since [tex]\( 6 > 3 \)[/tex], Charlie has traveled for a greater amount of time when his distance from New York stops decreasing and starts increasing.

Conclusion:
The correct answer is:

A. Charlie