Coplanarity of two lines

The vector equations of two lines are
$\overrightarrow{r}=3\hat{i}+5\hat{j}-7\hat{k}+\lambda (2\hat{i}-6\hat{j}+3\hat{k})$‍ and
$\overrightarrow{r}=5\hat{i}+\hat{j}-8\hat{k}+\mu (4\hat{i}-8\hat{j}+\hat{k})$‍,
where $\lambda$‍ and $\mu$‍ are parameters.