Vectors - Equations of Lines

The line \({{l}_{2}}\) passes through \(A\left( 3,1,-2 \right)\) and is parallel to the direction vector \(\left( \begin{matrix}7  \\15  \\1  \end{matrix} \right)\).

\({{l}_{2}}\) intersects \({{l}_{1}}:\mathbf{r}=\left( \begin{matrix}  -12  \\ -22  \\ 11  \end{matrix} \right)+\lambda \left( \begin{matrix}4  \\ 4  \\ -7  \end{matrix} \right);\lambda \in \mathbb{R}\) at \(C\).

Find

1. the coordinates of \(C\),
2. the acute angle between \({{l}_{1}}\) and \({{l}_{2}}\),
3. the vector line equation of mirror image of \({{l}_{2}}\) in \({{l}_{1}}\).