The set $$B= \left\lbrace \left[\begin{array}{c} -3\cr -3 \end{array}\right], \left[\begin{array}{c} 6\cr 14 \end{array}\right] \right\rbrace$$ is a basis for ${\mathbb R}^2$. Find the coordinates of the vector $\vec{x}= \left[\begin{array}{c} -9\cr -9 \end{array}\right]$ relative to the basis $B$.

$[\vec{x}]_B =$ $\left[\Rule{0pt}{2.4em}{0pt}\right.$$\left]\Rule{0pt}{2.4em}{0pt}\right.$