
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
The following are some two-digit subtraction operations: $21-12=9$, $31-13=18$, $32-23=9$, $42-24=18$, $14-41=-27$, $51-15=36$, $26-62=-36$, $\ldots$ Observing the above equations and their results, investigate a special case in two-digit subtraction operations:<br/>$(1)$ Write down another equation that fits the above pattern: ______;<br/>$(2)$ Use a letter to represent the pattern you observed: ______.

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