Show that all the rectangles with a given perimeter, the square has the largest area.

Explanation

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

### Step 1: Define the Variables
Let the length of the rectangle be \( L \) and the breadth be \( B \). The perimeter \( P \) of the rectangle is given by the formula:
\[ P = 2L + 2B \]

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