document.write( "Question 583241: An industrial rain gutter is constructed by folding the edges of a sheet of metal
\n" ); document.write( "20 inches wide so that the cross section of the gutter is a rectangle. How much edge
\n" ); document.write( "should be folded up on each side to maximize the area of the cross section?\r
\n" ); document.write( "\n" ); document.write( "im the picture it shows that it has 3 divisions the 2 sides and the base
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\n" ); document.write( "its problen two in this websiter
\n" ); document.write( "http://math.arizona.edu/~cjewell/112/homework/Homework13.pdf
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Algebra.Com's Answer #372446 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
An industrial rain gutter is constructed by folding the edges of a sheet of metal
\n" ); document.write( "20 inches wide so that the cross section of the gutter is a rectangle.
\n" ); document.write( " How much edge should be folded up on each side to maximize the area of the cross section?
\n" ); document.write( ":
\n" ); document.write( "End would look something like this |__|
\n" ); document.write( "Let the vertical sides = s
\n" ); document.write( "Let the horizontal = b
\n" ); document.write( "then
\n" ); document.write( "2s + b = 20 inches
\n" ); document.write( "b = (20-2s)
\n" ); document.write( "and
\n" ); document.write( "Area = s * b
\n" ); document.write( "replace b with (20-2s)
\n" ); document.write( "A = s(20-2s)
\n" ); document.write( "A = -2s^2 + 20s
\n" ); document.write( "This is a quadratic equation, we can find max area by finding the axis of symmetry. Formula: x = -b/(2a)
\n" ); document.write( "s = \"%28-20%29%2F%282%2A-2%29\"
\n" ); document.write( "s = +5 inches on each side will give the max area
\n" ); document.write( ":
\n" ); document.write( "Find the area
\n" ); document.write( "b = 20 - 2(5)
\n" ); document.write( "b = 10 is the base
\n" ); document.write( "A = 5 * 10
\n" ); document.write( "A = 50 sq/in is max area\r
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