To find the remaining loan amount after 9 years using the equation of the line of best fit \( y = 15413 - 1635x \), we'll substitute \( x = 9 \) into the equation.
\[ y = 15413 - 1635(9) \]
Calculating the value:
\[ y = 15413 - 1635 \times 9 \] \[ y = 15413 - 14715 \] \[ y = 698 \]
Therefore, the loan amount left after 9 years is $698.