document.write( "Question 120535: If the sides of a square are decreased by 3 cm, the area is decreased by 81cm^2. What were the dimensions of the original square? Could someone please help me, this has thrown me off! Thank you so much in advance. \n" ); document.write( "

Algebra.Com's Answer #88397 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Call the sides of the original square $\"x\"$
\n" ); document.write( "The area of the original square is $\"x%5E2\"$
\n" ); document.write( "When I decrease the sides by 3 cm, I have an area
\n" ); document.write( "of $\"%28x+-+3%29%28x+-+3%29\"$
\n" ); document.write( "In words:
\n" ); document.write( "81 cm^2 = (original area) - (area reduced by 3cm on each side)
\n" ); document.write( " $\"81+=+x%5E2+-+%28x+-+3%29%5E2\"$
\n" ); document.write( " $\"81+=+x%5E2+-+%28x%5E2+-+6x+%2B+9%29\"$
\n" ); document.write( " $\"6x+-+9+=+81\"$
\n" ); document.write( " $\"6x+=+90\"$
\n" ); document.write( " $\"x+=+15\"$
\n" ); document.write( "The original square is 15 cm x 15 cm
\n" ); document.write( " \n" ); document.write( "

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