The area of a square is calculated as length * width. Because all a square has all sides equal then we can say that given a side S, the area is S*S
For square A of sides A, the area is A*A=25 or A^2=25
Solving for A we know that A=<<5=5>>5
For square B of sides B, the area is B*B=81 or B^2=81
Solving for B we know that B=<<9=9>>9
The side difference between A and B is 9-5=<<9-5=4>>4
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