
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
Simplify first, then evaluate: $\frac{{a}^{2}-6ab+9{b}^{2}}{{a}^{2}-2ab}\div (\frac{5{b}^{2}}{a-2b}-a-2b)-\frac{1}{a}$, where $a$ and $b$ satisfy $\left\{\begin{array}{l}a+b=4\\ a-b=2\end{array}\right.$.

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