Ascatter plot containing the point (5,9) has the regression equation y = -x-3 (see photo)

The residual is the difference between the plotted point and the line of best fit.

We first need to know the point at x=5 for the line of best fit.
y1 = -(5) - 3 = -8

Now we need to find the difference between the line of best fit and the plotted point.
residual = 9 -(-8) = 9 + 8 = 17 or C

The answer simplified would be. -6300x