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After the side length of a square is reduced by 3 cm, the area will be reduced by 51 square cm. Find the original square area
Let the length of the original square be x cm
x×x-51=（x-3)(x-3)
We get x = 10
The area is 10 × 10 = 100 square centimeter
The side length of a square is reduced by 3 cm, and its area is reduced by 45 square cm. The original side length is equal to
Let the length of the original square be X
(X-3)(X-3)+45=X^2
X=9
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