Matrices & Systems · Medium problem

In the column picture, the vector $\begin{pmatrix}9\\8\\13\end{pmatrix}$ is written as $x\begin{pmatrix}1\\2\\1\end{pmatrix} + y\begin{pmatrix}2\\1\\3\end{pmatrix} + z\begin{pmatrix}1\\1\\2\end{pmatrix}$. Find $y$.