document.write( "Question 72608: Geometry. If the sides of a square are decreased by 2cmm the area is decreased by 36cm^2. What were the dimensions of the original square?: \r
\n" ); document.write( "\n" ); document.write( "I did not see how this was solved???
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Algebra.Com's Answer #51904 by bucky(2189)\"\" \"About 
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Let the original length of the side of the square be represented by L. Since the area of a
\n" ); document.write( "square equals the square of a side we can by letting A represent the original area write the
\n" ); document.write( "equation:
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\n" ); document.write( "\"A+=+L%5E2\"
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\n" ); document.write( "Now what happens when we decrease the length of the side by 2 cm? The new length of the side
\n" ); document.write( "is the old length minus 2 cm or L - 2. And we are told that the new area of the square is
\n" ); document.write( "old area A minus 36 square cm or A - 36. Now for the new square, let's write the area equation
\n" ); document.write( "that says the Area = the square of a side:
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\n" ); document.write( "\"A+-+36+=+%28L-2%29%5E2\"
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\n" ); document.write( "but we said previously that A is equal to \"L%5E2\". Substituting \"L%5E2\" for A into our
\n" ); document.write( "equation we get:
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\n" ); document.write( "\"L%5E2+-+36+=+%28L-2%29%5E2\"
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\n" ); document.write( "and by squaring the right side we get:
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\n" ); document.write( "\"L%5E2+-+36+=+L%5E2+-+4L+%2B+4\"
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\n" ); document.write( "Then you can subtract L^2 from both sides to reduce the equation to:
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\n" ); document.write( "\"-36+=+-4L+%2B+4\"
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\n" ); document.write( "Add 4L to both sides to get:
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\n" ); document.write( "\"4L+-+36+=+4\"
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\n" ); document.write( "Then add 36 to both sides:
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\n" ); document.write( "\"4L+=+40\"
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\n" ); document.write( "Finally, divide both sides by 4 to end up with \"L+=+10\" and the answer is in cm. So the
\n" ); document.write( "dimensions of the original square (represented by L) were 10 cm on a side.
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\n" ); document.write( "Hope this untangles the problem for you and helps you to see how to deal with problems such
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