
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
Two identical resistors, each with resistance \( R \), are connected in series and attached to a DC voltage source \( U \). An ideal voltmeter is connected in parallel with one of the resistors, and its reading is \( U_{v} = 15 \text{ V} \). Afterward, the voltmeter is replaced with an ideal ammeter, and the ammeter reading \( I_{A} = 20 \text{ A} \). Determine the value of \( R \). 

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