Hey! Let me help you on this one.
In order for us to solve this problem, let's break it apart first.

is congruent to

, or in other words, they are the same.
As it stated, perimeter of

is 12 feet, and just like we mentioned before, both of these figures are perfectly congruent.
This means that both of these figures have the same perimeter as well!
Answer: The perimeter of CBD is 12 feet.