document.write( "Question 407949: Glen cuts half a rectangular lawn, 40 m by 30 m, by mowing strips of equal width around the perimeter. Brad cuts the small rectangle left. How wide a strip does Glen cut so that they share the work equally? \n" ); document.write( "
Algebra.Com's Answer #287443 by ankor@dixie-net.com(22740)\"\" \"About 
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Glenn cuts half a rectangular lawn, 40 m by 30 m by mowing strips of equal width around the perimeter.
\n" ); document.write( " Brad cuts the smalle rectangle left.
\n" ); document.write( " How wide a strip does Glenn cut so that they share the work equally?
\n" ); document.write( ":
\n" ); document.write( "Find the total area of the lawn:
\n" ); document.write( "40 * 30 + 1200 sq/m
\n" ); document.write( "then
\n" ); document.write( "600 sq/m = half the lawn
\n" ); document.write( ":
\n" ); document.write( "Let x = the width of the strip cut by Glenn to leave half the lawn for Brad
\n" ); document.write( ":
\n" ); document.write( "(40-2x)*(30-2x) = 600
\n" ); document.write( "FOIL
\n" ); document.write( "1200 - 80x - 60x + 4x^2 = 600
\n" ); document.write( "Arrange as a quadratic equation
\n" ); document.write( "4x^2 - 140x + 1200 - 600 = 0
\n" ); document.write( "4x^2 - 140x + 600 = 0
\n" ); document.write( "Simplify, divide by 4
\n" ); document.write( "x^2 - 35x + 150 = 0
\n" ); document.write( "Factors to:
\n" ); document.write( "(x-5)(s-30) = 0
\n" ); document.write( "Two solutions, but only one will be reasonable
\n" ); document.write( "x = 5 meter strip cut around the outside of the lawn leaves half for Brad
\n" ); document.write( ";
\n" ); document.write( ":
\n" ); document.write( "Check that; (subtract 2(5) from each dimension):
\n" ); document.write( "1200 - (30 * 20) = 600 \n" ); document.write( "
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