There are many shapes that can be constructed from 12 matches.
If our unit of length is 1 match, in the image I show 2 such shapes: One with area of 9 square matches, and one with area of 5 square matches.
Can you build a shape with 12 match perimeter and area of 4 square matches?
Reasonable rules apply: it has to be a perimeter, and full lengths of matches must be used.