Select the correct answer.

Annabeth and Charlie are both on road trips. Annabeth's distance, in miles, from New York 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 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. This cannot be determined from the given information.
C. They will have traveled the same amount of time.
D. Annabeth



Answer :

To solve this problem, we need to understand how the distances for Annabeth and Charlie change over time.

1. Annabeth's Distance Equation Analysis:
Annabeth's distance from New York is given by the function:
[tex]\[ D(t) = 60|t-3| \][/tex]
This equation describes a V-shaped graph with the vertex (the lowest point) at [tex]\( t = 3 \)[/tex]. Prior to [tex]\( t = 3 \)[/tex], the distance decreases as time approaches 3, and after [tex]\( t = 3 \)[/tex], the distance increases as time moves away from 3. Therefore, Annabeth's distance stops decreasing and starts increasing at [tex]\( t = 3 \)[/tex] hours. Thus, Annabeth travels for [tex]\( 3 \)[/tex] hours before her distance starts increasing.

2. Charlie's Distance Table Analysis:
Charlie's distance from New York is provided in 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 this table, we observe the following distances at various times:
- At [tex]\( t = 0 \)[/tex] hours, Charlie is 270 miles away.
- At [tex]\( t = 2 \)[/tex] hours, Charlie is 180 miles away.
- At [tex]\( t = 4 \)[/tex] hours, Charlie is 90 miles away.
- At [tex]\( t = 6 \)[/tex] hours, Charlie is 0 miles away.
- At [tex]\( t = 8 \)[/tex] hours, Charlie is 90 miles away again.
- At [tex]\( t = 10 \)[/tex] hours, Charlie is 180 miles away again.

From the table, the distance [tex]\( F(t) \)[/tex] is decreasing until [tex]\( t = 6 \)[/tex] hours and then starts increasing. So, Charlie's distance stops decreasing and starts increasing at [tex]\( t = 6 \)[/tex] hours. Thus, Charlie travels for [tex]\( 6 \)[/tex] hours before his distance starts increasing.

Conclusion:
Annabeth travels for [tex]\( 3 \)[/tex] hours, while Charlie travels for [tex]\( 6 \)[/tex] hours before their distances from New York stop decreasing and start increasing. Therefore, Charlie has travelled for a greater amount of time before his distance starts increasing.

The correct answer is:
A. Charlie

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