Question 120047: if the sides of a square are decreased by 3 cm, the area is decreased by 81 cm^2. what were the dimensions of the original square? Answer by checkley71(8403) (Show Source):
You can put this solution on YOUR website! (x-3)^2=x^2-81
x^2-6x+9=x^2-81
-6x=-81-9
-6x=-90
x=-90/-6
x=15 answer for the sides opf the original square.
proof:
(15-3)^2=15^2-81
12^2=225-81
144=144
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