SOLUTION: The area of a square is 81 square centimeters. If the same amount is added to one dimension and removed from the other, the resulting rectangle has an area 9 square centimeters les
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Question 313815: The area of a square is 81 square centimeters. If the same amount is added to one dimension and removed from the other, the resulting rectangle has an area 9 square centimeters less than the area of the square. How much is added and subtracted? Answer by unlockmath(1688) (Show Source):
You can put this solution on YOUR website! Hello,
We know that the measure of the square is 9 cm by 9 cm. Let's represent each side as "x". Let's represent the amount added and subtracted as "y". The equation that can be set up is:
x^2-9=(x+y)(x-y) This can be rewritten as:
x^2-9=x^2-y^2 The x^2 cancels out leaving us:
-9=-y^2 Divide by -1 and sq rt to get:
y=3
Therefore we can solve this rectangle size as 12 cm by 6 cm. The area comes out to be 72 cm^2. It works out.
Makes sense?
RJ
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