document.write( "Question 1170798: The perimeter of a rectangular fields is 200m. If the length were reduced 20m and the width reduced by 25%, the perimeter would be reduced by 30%. The original length of the field is: \n" ); document.write( "

Algebra.Com's Answer #795681 by VFBundy(438) $\"\"$ $\"About$

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Original length = L
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\n" ); document.write( "2L + 2W = 200
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\n" ); document.write( "2(L - 20) + 2(0.75W) = 0.70(200)
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\n" ); document.write( "2L - 40 + 1.5W = 140
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\n" ); document.write( "2L + 1.5W = 180
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\n" ); document.write( "1.5W = 180 - 2L
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\n" ); document.write( "W = 180/1.5 - 2L/1.5
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\n" ); document.write( "W = 120 - 2L/1.5
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\n" ); document.write( "W = 120 - 4L/3
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\n" ); document.write( "Plug W = 120 - 4L/3 into the first equation:
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\n" ); document.write( "2L + 2W = 200
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\n" ); document.write( "2L + 2(120 - 4L/3) = 200
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\n" ); document.write( "2L + 240 - 8L/3 = 200
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\n" ); document.write( "2L - 8L/3 = -40
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\n" ); document.write( "6L/3 - 8L/3 = -40
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\n" ); document.write( "-2L/3 = -40
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\n" ); document.write( "-2L = -120
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\n" ); document.write( "L = 60
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\n" ); document.write( "Original length = L = 60m \n" ); document.write( "

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