Pentagons with specific angles.

Question

I have a series of pentagons (let's call them sepentagons) with the following characteristics:

• At one vertex, the internal angle is 60 degrees
• All other vertexes have an internal angle of 120 degrees
• The length of each side is an integer

• The two sides that meet at 60 degrees are the same length

  1. What are all sepentagons that the longest edge is 5 cm?

Answer 1

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