Question

Dry rectangle that has an area of a square you need any permitter of 12 units what are the silence of the rectangle

Answer 1

Please review your questions before posting them.  Your spelling makes it necessary for the reader to try to guess what you mean.

If you meant that the perimeter (not permitter) of a square is 12 units, then the length of one side (not silence) of the rectangle is (12 units)/4 = 3 units.