If a line has the direction ratios $-18, 12, -4,$ then what are its direction cosines?

Question

$\begin{array}{1 1} \bigg( \large\frac{9}{11},\large \frac{6}{11}, \large\frac{-2}{11} \bigg) \\ \bigg( \large\frac{-9}{11},\large \frac{6}{11}, \large\frac{-2}{11} \bigg) \\ \bigg( \large\frac{-9}{11},\large \frac{6}{11}, \large\frac{2}{11} \bigg) \\ \bigg( \large\frac{-9}{11},\large \frac{-6}{11}, \large\frac{-2}{11} \bigg) \end{array} $