[tex]\begin{array}{cccccccc}\\ \underline{-3}&,&12&,&-33&,&102\\ \cline{1-7} &&(-3)(\underline{-3})+3&&(-3)(12)+3&&(-3)(-33)+3 \end{array} \\\\[-0.35em] ~\dotfill\\\\ \begin{array}{ccc} -303&,&912\\ \cline{1-3} (-3)(102)+3&&(-3)(-303)+3 \end{array}[/tex]