document.write( "Question 94986: If the sides of a square are decreased by 2 cm, the area is decreased by 36 cm2. What were the dimensions of the original square?\r
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Algebra.Com's Answer #69161 by ankor@dixie-net.com(22740)\"\" \"About 
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If the sides of a square are decreased by 2 cm, the area is decreased by 36 cm2. What were the dimensions of the original square?
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\n" ); document.write( "Let x = side of original square
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\n" ); document.write( "(x-2) = side of the new square
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\n" ); document.write( "Original square area - new square area = 36
\n" ); document.write( " x^2 - (x-2)^2 = 36
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\n" ); document.write( " x^2 - (x^2 - 4x + 4) = 36: FOILed (x-2)(x-2)
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\n" ); document.write( " x^2 - x^2 + 4x - 4 = 36; removing bracket changes the signs
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\n" ); document.write( "4x = 36 + 4; x^2's cancel out
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\n" ); document.write( "4x = 40
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\n" ); document.write( "x = 40/4
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\n" ); document.write( "x = 10 cm, side of original square:
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\n" ); document.write( "Check: 10^2 - 8^2 = 36 \n" ); document.write( "
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