Vector Algebra

Let $\vec{a}, \vec{b}$ and $\vec{c}$ be three non-zero vectors such that $\vec{b}$ and $\vec{c}$ are non-collinear. If $\vec{a}+5 \vec{b}$ is collinear with $\vec{c}, \vec{b}+6 \vec{c}$ is collinear with $\vec{a}$ and $\vec{a}+\alpha \vec{b}+\beta \vec{c}=\overrightarrow{0}$, then $\alpha+\beta$ is equal to