Show that of all the rectangles of given area, the square has the smallest perimeter.

Explanation

To show that of all rectangles with a given area, the square has the smallest perimeter, we can follow these steps:

### Step 1: Define the Variables
Let the dimensions of the rectangle be \( x \) and \( y \). The area \( A \) of the rectangle is given by:
\[ A = x \cdot y \]
This area is fixed.
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