
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Xiao Liang solved the system of equations $\begin{cases} 2x+y=\bullet \\ 2x-y=12 \end{cases}$ and found the solution $\begin{cases} x=5 \\ y=\star \end{cases}$. Unfortunately, two drops of ink covered the numbers $\bullet$ and $\star$. Please help him find the number $\star$, $\star=$ ______.

Present the answer in LaTex format: \boxed{Your answer}
user