document.write( "Question 1124149: Sue used 54 ft of forming and 24 cubic ft of concrete to pour a sidewalk 4 inches thick. Assuming that the length is the larger of the dimensions, what was the length of the sidewalk? \n" ); document.write( "
Algebra.Com's Answer #740595 by ankor@dixie-net.com(22740)\"\" \"About 
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used 54 ft of forming and 24 cubic ft of concrete to pour a sidewalk 4 inches thick.
\n" ); document.write( " Assuming that the length is the larger of the dimensions, what was the length of the sidewalk?
\n" ); document.write( ":
\n" ); document.write( "let L = the length of the side walk
\n" ); document.write( "let w = the width
\n" ); document.write( "The forming is the perimeter of the side walk
\n" ); document.write( "2L + 2w = 54
\n" ); document.write( "Simplify, divide by 2
\n" ); document.write( "L + w = 27
\n" ); document.write( "w = (-L+27), we can use this form for substitution
\n" ); document.write( ":
\n" ); document.write( "We can find area of the concrete by dividing by the depth, 4\" which is \"1%2F3\" ft
\n" ); document.write( "24 divided by 1/3 = 72 sq/ft
\n" ); document.write( "therefore the area equation
\n" ); document.write( "L*w = 72
\n" ); document.write( "replace w with (-L+27)
\n" ); document.write( "L(-L+27) = 72w
\n" ); document.write( "a quadratic equation
\n" ); document.write( "-L^2 + 27L - 72 = 0
\n" ); document.write( "Multiply equation by -1
\n" ); document.write( "L^2 - 27L + 72 = 0
\n" ); document.write( "Factors to
\n" ); document.write( "(L-3)(L-24) = 0
\n" ); document.write( "L = 24 ft is the length of sidewalk
\n" ); document.write( ":
\n" ); document.write( ";
\n" ); document.write( "Confirm this by finding the perimeter (forming). Width is 3 ft
\n" ); document.write( "2(24) + 2(3) = 54 \n" ); document.write( "
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