document.write( "Question 449621: You have a rectangle 20ft by 30ft and you want to double it in size?
\n" ); document.write( "What is the new area? How much do you increase each side by showing the answer as a function of x?\r
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Algebra.Com's Answer #309377 by ankor@dixie-net.com(22740)\"\" \"About 
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You have a rectangle 20ft by 30ft and you want to double it in size?
\n" ); document.write( "What is the new area?
\n" ); document.write( "How much do you increase each side by showing the answer as a function of x?
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\n" ); document.write( "The new area: 2(20*30) = 1200 sq/ft
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\n" ); document.write( "Let x = increase in length and width to double the area
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\n" ); document.write( "The Area equation:
\n" ); document.write( "(x+20)*(x+30) = 1200
\n" ); document.write( "FOIL
\n" ); document.write( "x^2 + 30x + 20x + 600 = 1200
\n" ); document.write( "Combine like terms
\n" ); document.write( "x^2 + 50x + 600 - 1200 = 0
\n" ); document.write( "x^2 + 50x - 600 = 0
\n" ); document.write( "Factors
\n" ); document.write( "(x+60)(x-10) = 0
\n" ); document.write( "the positive solution is all we want here
\n" ); document.write( "x = 10 ft increase in the length and width
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\n" ); document.write( "Check that: (10+20) * (10+30) = 1200 \n" ); document.write( "
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