Matrices And Determinants

Let \(\lambda, \mu \in \mathbf{R}\). If the system of equations

$$\begin{aligned} & 3 x+5 y+\lambda z=3 \\ & 7 x+11 y-9 z=2 \\ & 97 x+155 y-189 z=\mu \end{aligned}$$

has infinitely many solutions, then \(\mu+2 \lambda\) is equal to :