document.write( "Question 184171: If the sides of a square are lenghtened by 8cm, the area becomes 144 cm^2. Find the length of a side of the original square. \r
\n" ); document.write( "\n" ); document.write( "Which form of the quadratic equation would I use to solve this problem? \n" ); document.write( "
Algebra.Com's Answer #138202 by ankor@dixie-net.com(22740)\"\" \"About 
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If the sides of a square are lengthened by 8cm, the area becomes 144 cm^2.
\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+8) = side of the larger square
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\n" ); document.write( "(x+8)^2 = 144
\n" ); document.write( "Find the square root of both sides
\n" ); document.write( "x + 8 = 12
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\n" ); document.write( "x = 12 - 8
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\n" ); document.write( "x = 4 cm is the length of the original square
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\n" ); document.write( "Check: (4+8)^2 = 144
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\n" ); document.write( "If you absolutely have to have a quadratic equation:
\n" ); document.write( "Foil (x+8)^2
\n" ); document.write( "x^2 + 16x + 64 = 144
\n" ); document.write( "x^2 + 16x + 64 - 144 = 0
\n" ); document.write( "x^2 + 16x - 80 = 0
\n" ); document.write( "Factor
\n" ); document.write( "(x+20)(x-4) = 0
\n" ); document.write( "Positive solution is what we want:
\n" ); document.write( "x = 4 cm \n" ); document.write( "
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