document.write( "Question 750169: A 30 cm piece of wire is cut into two pieces. One piece is bent into the shape of a square the other piece is bent into the shape of a rectangle with length to width ratio of 2:1 What are the length's of the two pieces if the sum of the areas of the square and rectangle is a minimum?\r
\n" ); document.write( "\n" ); document.write( "Can you please help me out? Thanks so much in advance:)
\n" ); document.write( "Can you also show the steps it would really help me understand better:)
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Algebra.Com's Answer #456465 by ankor@dixie-net.com(22740)\"\" \"About 
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A 30 cm piece of wire is cut into two pieces.
\n" ); document.write( " One piece is bent into the shape of a square. the other piece is bent into
\n" ); document.write( " the shape of a rectangle with length to width ratio of 2:1
\n" ); document.write( " What are the length's of the two pieces if the sum of the areas of the square
\n" ); document.write( " and rectangle is a minimum?
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\n" ); document.write( "let x = length of the side of square
\n" ); document.write( "let y = length of the width of the rectangle
\n" ); document.write( "then
\n" ); document.write( "2y = Length of rectangle
\n" ); document.write( "So we have
\n" ); document.write( "4x + 2(2y) + 2(y) = 30
\n" ); document.write( "4x + 6y = 30
\n" ); document.write( "6y = 30 - 4x
\n" ); document.write( "simplify, divide by 2
\n" ); document.write( "3y = 15 - 2x
\n" ); document.write( "Divide by 3
\n" ); document.write( "y = (5-\"2%2F3\"x)
\n" ); document.write( "the total area equation
\n" ); document.write( "A = x^2 + (2y*y)
\n" ); document.write( "A = x^2 + 2y^2
\n" ); document.write( "replace y with (5-\"2%2F3\"x) which is (5-.67x)
\n" ); document.write( "A = x^2 + 2(5-.67x)^2
\n" ); document.write( "FOIL (5-.67x)(5-.67x)
\n" ); document.write( "A = x^2 + 2(25-6.7x+.44x^2)
\n" ); document.write( "A = x^2 + 50 - 13.14x + .88x^2
\n" ); document.write( "A = 1.88x^2 - 13.14x + 50
\n" ); document.write( "Find the minimum by finding the axis of symmetry using x = -b/(2a)
\n" ); document.write( "x = \"%28-%28-13.14%29%29%2F%282%2A1.88%29\"
\n" ); document.write( "x = \"13.14%2F3.76\"
\n" ); document.write( "x = 3.5 cm is the side of the square for minimum area, therefore
\n" ); document.write( "4(3.5) = 14 cm is piece made into a square
\n" ); document.write( "Find the piece made into the rectangle
\n" ); document.write( "y = 5 - .67(3.5)
\n" ); document.write( "y = 2.66 cm is the width of the rectangle, therefore
\n" ); document.write( "6(2.66) ~ 16 cm is the piece made into the rectangle
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