
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
In triangle $ABC$, $\cos B = -\frac{5}{13}$ and $\cos C = \frac{4}{5}$.
1. Find the value of $\sin A$.
2. Given that the area of $\triangle ABC$, $S_{\triangle ABC}$, is $\frac{33}{2}$, find the length of $BC$.

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