These formulas describe the basic properties of a square, including its perimeter, area, and diagonal length. The side length is denoted by \(a\).
\[ P = 4 \times a \]
Perimeter (P): The total length around the square.
\[ A = a^2 \]
Area (A): The total surface enclosed within the square.
\[ d = a \times \sqrt{2} \]
Diagonal (d): The length of the diagonal across the square, derived from the Pythagorean theorem.
