document.write( "Question 610085: a rectangular skating rink measuring 30 m by 20 m is to be doubled in area by adding a strip at one end and a strip of the same width along one side. find the width of the strips \n" ); document.write( "
Algebra.Com's Answer #384250 by ankor@dixie-net.com(22740)\"\" \"About 
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a rectangular skating rink measuring 30 m by 20 m is to be doubled in area by adding a strip at one end and a strip of the same width along one side.
\n" ); document.write( "find the width of the strips
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\n" ); document.write( "Find the original area: 30 * 20 = 600
\n" ); document.write( "Find the doubled area: 2 * 600 = 1200 sq/m
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\n" ); document.write( "Let x = the length of the strip on end and on the side
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\n" ); document.write( "(x+30)*(x+20) = 1200
\n" ); document.write( "x^2 + 20x + 30x + 600 - 1200 = 0
\n" ); document.write( "x^2 + 50x - 600 = 0
\n" ); document.write( "Factors to
\n" ); document.write( "(x + 60)(x - 10) = 0
\n" ); document.write( "the positive solution all we want here
\n" ); document.write( " x = 10 meters is the width of the strips
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\n" ); document.write( "Check this
\n" ); document.write( "(10+30) + (10+20) = 1200 \n" ); document.write( "
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