Our hint here is the identity of the shape. It is mentioned that the shape is a square. By definition, a square is a two-dimensional with four sides having equal measures. The formula for its area is:
A = s², where s is the length of its side
Substituting the value of A,
25/36 in² = s²
s = √(25/36)
s = 5/6 inches or 0.833 inches