document.write( "Question 177370: If the sides of a square are lengthened by 7cm, the area becomes 121 cm squared. Find the length of a side of the original square.\r
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Algebra.Com's Answer #132465 by ankor@dixie-net.com(22740)\"\" \"About 
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If the sides of a square are lengthened by 7cm, the area becomes 121 cm squared.
\n" ); document.write( " Find the length of a side of the original square.
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\n" ); document.write( "let x = side of the original square
\n" ); document.write( "then
\n" ); document.write( "(x+7) = side of the larger square which = 121 sq/cm
\n" ); document.write( "we can write this like this:
\n" ); document.write( "(x+7)^2 = 121
\n" ); document.write( "FOIL
\n" ); document.write( "x^2 + 14x + 49 = 121
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\n" ); document.write( "x^2 + 14x + 49 - 121 = 0
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\n" ); document.write( "x^2 + 14x - 72 = 0
\n" ); document.write( "Factor
\n" ); document.write( "(x + 18)(x - 4) = 0
\n" ); document.write( "Positive solution
\n" ); document.write( "x = 4 cm, size of the original square
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\n" ); document.write( "Check: (4+7)^2 = 121
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\n" ); document.write( "did this make sense to you now?
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