Answer
The fifth column is the multiple of the fourth column by $-1$.
Work Step by Step
Given $$
\left|\begin{array}{rrrrr}{4} & {3} & {1} & {9} & {9} \\ {9} & {-1} & {2} & {3} & {-3} \\ {3} & {4} & {6} & {9} & {12} \\ {5} & {2} & {0} & {6} & {6} \\ {6} & {0} & {3} & {0} & {0}\end{array}\right|=0.
$$
The fifth column is the multiple of the fourth column by $-1$.