Question 31069
Assume that the length of smaller square is x inch
The length of the larger square is then (x+3)

Area of smaller Square = x^2
Area of larger Square=(x+3)^2

Based on the question,

(x+3)^2 = x^2 + 51
=>x^2 + 6x + 9 = x^2 + 51
=>6x = 42
=>x = 7

Length of the sides of the smaller square is 7 inch and the length of the side of the larger square is 10 inch.