document.write( "Question 487863: I'm having trouble with this word problem, please help :)\r
\n" ); document.write( "\n" ); document.write( "The length of a certain lot is 20 feet less than four times its width. The area is 4200 sq. ft. What are the dimensions of the lot? \n" ); document.write( "
Algebra.Com's Answer #333164 by stanbon(75887)\"\" \"About 
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The length of a certain lot is 20 feet less than four times its width. The area is 4200 sq. ft. What are the dimensions of the lot?
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\n" ); document.write( "Let the width be W.
\n" ); document.write( "Then the length is 4W-20
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\n" ); document.write( "Equation:
\n" ); document.write( "Area = length*width
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\n" ); document.write( "W(4W-20) = 4200
\n" ); document.write( "4W^2 - 20W - 4200 = 0
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\n" ); document.write( "W^2 - 5W - 1050 = 0
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\n" ); document.write( "Factor:
\n" ); document.write( "W = [5 +- sqrt(25 - 4*-1050)]/2
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\n" ); document.write( "W = [5 +- sqrt(4225)]/2
\n" ); document.write( "W = [5 +- 65]/2
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\n" ); document.write( "Positive solution:
\n" ); document.write( "W = 35 (width)
\n" ); document.write( "Length = 4*35-20 = 120
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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