
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 shapes are composed of unit squares. The first shape is a rectangle that measures 7 units in length and 3 units in height. The second shape is also a rectangle, but it has internal segments creating a grid of 6 equal rectangles, each 1 unit in height and 2 units in length. What is the positive difference of their perimeters, in units?

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