we know that
Of all the rectangles having same area, square has the least perimeter
area of square=x²
where
x is the length side of the square
A=72 cm²
72=x²
x=√72-----> x=6√2 cm
Perimeter of square=4*x------> 4*(6√2)-----> P=24√2 cm
P=33.94 cm
the answer is
the perimeter is equal to 24√2 cm or 33.94 cm