To find the value of the car after 5 years using the function \( y = 21,000(1 - 0.15)^x \), we will substitute \( x \) with 5:
\[ y = 21,000(1 - 0.15)^5 \]
First, calculate \( 1 - 0.15 \):
\[ 1 - 0.15 = 0.85 \]
Now, raise this value to the power of 5:
\[ 0.85^5 \approx 0.4437 \]
Next, multiply this result by 21,000:
\[ y \approx 21,000 \times 0.4437 \approx 9,316.77 \]
Rounding to the nearest dollar:
\[ y \approx 9,317 \]
Therefore, the value of the car after 5 years is approximately $9,318.
So the correct response is:
$9,318.