geometry
posted by Anonymous .
a piece of rectangular sheet metal is 20 in. wide. It is made into a rain gutter by turning up the edges to form parallel sides. Let x represent the length of each of the parallel side.
(a)give the restrictions on x
(b)determine a fuction A that gives the area of a cross section of the gutter.
(c) For what value of x will A be a maximum (and thus minimize the amount of water that the gutter will hold)? what is this maximum area?
(d) for what values of x will the area of a cross section be less than 10 in.^2?

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