Question 1138434
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All squares are similar.<br>
If the ratio of the areas of two squares is 1:16, then the ratio of the lengths of the sides of the two squares is 1:4.<br>
If increasing the side length by 9 inches multiplies the side length by 4, then those 9 inches are 3 times the original side length; so the original side length is 9/3 = 3 inches.