Solve the Problem
-A Piece of Rectangular Sheet Metal Is $x$

Multiple Choice

Solve the problem
-A piece of rectangular sheet metal is 17 inches wide. It is to be made into a rain gutter by turning up equal edges to form parallel sides. Let $x$ represent the length of each of the parallel sides. For what value of $x$ will the area of the cross section be a maximum (and thus maximize the amount of water that the gutter will hold) ? If necessary, round to 2 decimal places.

A) $8.5 \mathrm { in }$ .
B) $4.25 \mathrm { in }$ .
C) $68 \mathrm { in }$ .
D) $34 \mathrm { in }$ .