Answer:
6 inches
Explanation:
Let s represent the length of the side of the square in inches. Then the rectangle dimensions are ...
length: s + 3
width: s - 2
The area of the rectangle is the product of these, so is ...
(s +3)(s -2) = s² +s -6
This is the same as the area of the square, which is s², so we have ...
s² = s² +s -6 . . . . square area = rectangle area
0 = s - 6 . . . . . . . subtract s²
6 = s . . . . . . . . . . add 6
The side of the square is 6 inches.
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Check
The area of the square is 6² = 36.
The area of the rectangle is 9×4 = 36. (answer meets problem conditions)