For three vectors $\vec{A}=(-x \hat{\imath}-6 \hat{\jmath}-2 \hat{k}), \vec{B}=(-\hat{\imath}+4 \hat{\jmath}+3 \hat{k})$ and $\vec{C}=(-8 \hat{\imath}-\hat{\jmath}+3 \hat{k})$, if $\overrightarrow{\mathrm{A}} \cdot(\overrightarrow{\mathrm{B}} \times \overrightarrow{\mathrm{C}})=0$, them value of x is