
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 the expression: $\frac{x^2-4x}{x^2-16}÷\frac{x^2+4x}{x^2+8x+16}-\frac{2x}{x-4}$, then choose a suitable value for $x$ from $-4$, $-2$, $0$, $4$ to substitute and evaluate.

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