Two congruent pentagons are each formed by removing a right-angled isosceles triangle from a square of side-length 1. The two pentagons are then fitted together as shown.
What is the length of the perimeter of the octagon formed?
Select one option, then click Submit.
4
4 + 2\sqrt{2}
5
6 - 2\sqrt{2}
6
Select an option, then submit.
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