document.write( "Question 92555: Geomatry. If the sides of a square are decreased by 2cm, the area is decreased by 36cm^2 \n" ); document.write( "
Algebra.Com's Answer #67375 by bucky(2189)\"\" \"About 
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Let x be the length of the side of the original square. Therefore, the area of the original
\n" ); document.write( "square is x^2.
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\n" ); document.write( "Now take 2 cm off each side of the original square. That means that the length of the side
\n" ); document.write( "of the new square is x-2 cm. You square this to get the area of this new square. So the
\n" ); document.write( "area of the new square is:
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\n" ); document.write( "\"%28x-2%29%5E2+=+x%5E2+-4x+%2B+4\"
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\n" ); document.write( "The problem then says that the difference between the original area \"%28x%5E2%29\" and the new
\n" ); document.write( "area \"%28x%5E2+-+4x+%2B4%29\" is 36 cm^2. Setting this up as an equation we have:
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\n" ); document.write( "\"x%5E2+-+%28x%5E2+-+4x+%2B4%29+=+36\"
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\n" ); document.write( "Since the parentheses are preceded by a minus sign, you can remove the parentheses
\n" ); document.write( "by changing the signs of the terms within the parentheses. This leads to:
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\n" ); document.write( "\"x%5E2+-+x%5E2+%2B+4x+-+4+=+36\"
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\n" ); document.write( "Note that the \"x%5E2\" terms cancel each other due to their difference in signs. So
\n" ); document.write( "they drop from the equation which then becomes:
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\n" ); document.write( "\"4x+-+4+=+36\"
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\n" ); document.write( "Get rid of the -4 on the left side by adding +4 to both sides. This reduces the equation to:
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\n" ); document.write( "\"4x+=+40\"
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\n" ); document.write( "Solve for x by dividing both sides by 4 to get:
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\n" ); document.write( "\"x+=+40%2F4+=+10\"
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\n" ); document.write( "So the length of each side of the original square is 10 cm.
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\n" ); document.write( "And the length of each side of the new square is 10 - 2 or 8 cm.
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\n" ); document.write( "Check. The area of the original square is 10*10 = 100 cm^2. The area of the new square is
\n" ); document.write( "8 * 8 = 64 cm^2.
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\n" ); document.write( "The difference in their areas is 100 cm^2 - 36 cm^2 = 64 cm^2.
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\n" ); document.write( "Hope that the answer you were looking for is in here somewhere. This will probably
\n" ); document.write( "give you the process you can use to solve this problem.
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