document.write( "Question 1012461: A piece of wire 6 metres long is cut into 2 parts. One part is used to form a square and the other to make a rectangle whose length is 3 times its breadth. Find the lengths of the 2 parts if the sum of the two areas is a minimum. \n" ); document.write( "
Algebra.Com's Answer #628414 by ankor@dixie-net.com(22740)\"\" \"About 
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A piece of wire 6 metres long is cut into 2 parts.
\n" ); document.write( " One part is used to form a square and the other to make a rectangle whose length is 3 times its breadth.
\n" ); document.write( " Find the lengths of the 2 parts if the sum of the two areas is a minimum.
\n" ); document.write( ":
\n" ); document.write( "let s = the side of the square
\n" ); document.write( "let L = the length of the rectangle
\n" ); document.write( "let W = the width
\n" ); document.write( "therefore the two perimeters = 6
\n" ); document.write( "4s + 2L + 2W = 6
\n" ); document.write( "Simplify, divide equation by 2
\n" ); document.write( "2s + L + W = 3
\n" ); document.write( "Given that
\n" ); document.write( "L = 3W
\n" ); document.write( "therefore
\n" ); document.write( "2s + 3W + W = 3
\n" ); document.write( "2s + 4W = 3:
\n" ); document.write( "Simplify, divide by 2
\n" ); document.write( "s + 2W = 1.5
\n" ); document.write( "s = -2W+1.5
\n" ); document.write( ":
\n" ); document.write( "the total area
\n" ); document.write( "A = s^2 + LW
\n" ); document.write( "Replace s with (-2W+1.5), replace L with 3W
\n" ); document.write( "A = (-2W+1.5)^2 + 3W(W)
\n" ); document.write( "FOIL
\n" ); document.write( "A = 4W^2 - 3W - 3W + 2.25 + 3W^2
\n" ); document.write( "Combine like terms
\n" ); document.write( "A = 7W^2 - 6W + 2.25
\n" ); document.write( "Find the minimum by finding the axis of symmetry, x=-b/(2a)
\n" ); document.write( "w = \"%28-%28-6%29%29%2F%282%2A7%29\"
\n" ); document.write( "W = \"6%2F14\"
\n" ); document.write( "W = .42857 is the width for minimum area
\n" ); document.write( "Find L
\n" ); document.write( "3(.42857) = 1.2857 is the length
\n" ); document.write( "Find the length of the portion made into a rectangle (perimeter)
\n" ); document.write( "P = 2(1.2857 + 2(.42857)
\n" ); document.write( "P = 3.42856m is the portion made into a rectangle
\n" ); document.write( "then
\n" ); document.write( " 6 - 3.42856 = 2.57m is the portion made into a square
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