document.write( "Question 870992: How wide a border of uniform width should be added to a rectangle that is 8 ft by 12 ft in order to double the area? \n" ); document.write( "
Algebra.Com's Answer #525245 by mananth(16946)\"\" \"About 
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Let the width be x
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\n" ); document.write( "Length of rectangle 12 feet
\n" ); document.write( "width of rectangle 8 feet
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\n" ); document.write( "Area = 96 m^2
\n" ); document.write( "Area of plot 192 m^2
\n" ); document.write( "length of rectangle & plot 12 + 2 x
\n" ); document.write( "width of rectangle & plot 8 + 2 x
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\n" ); document.write( "( 12 + 2 x ) ( 8 + 2 x ) + -96 = 192
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\n" ); document.write( " 96 + 24 x + 16 x + 4 X^2 + -96 = 192
\n" ); document.write( " 4 X^2 + 40 x -192 =0
\n" ); document.write( "4x^2-16x+56x-192=0\r
\n" ); document.write( "\n" ); document.write( "4x(x-4)+56(x-4)=0\r
\n" ); document.write( "\n" ); document.write( "(x-4)(4x+56)=0
\n" ); document.write( "x=4 OR -14
\n" ); document.write( "ignore negative\r
\n" ); document.write( "\n" ); document.write( "width = 4 feet \n" ); document.write( "
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