A rectangular area adjacent to a river is to be fenced in; no fence is needed on the river side. The enclosed area is to be 1000 square feet. Fencing for the side parallel to the river is $5 per linear foot, and fencing for the other two sides is $8 per linear foot; the four corner posts are $25 apiece. Let x be the length of one of the sides perpendicular to the river.
a.) Find the dimensions of the cheapest enclosure.

Question

A rectangular area adjacent to a river is to be fenced in; no fence is needed on the river side. The enclosed area is to be 1000 square feet. Fencing for the side parallel to the river is $5 per linear foot, and fencing for the other two sides is $8 per linear foot; the four corner posts are $25 apiece. Let x be the length of one of the sides perpendicular to the river.
a.) Find the dimensions of the cheapest enclosure.

directrix · Answer

Quite similar problem to help you get started http://openstudy.com/study#/updates/51859371e4b0bc9e008a62d0

directrix · Answer

Work on the link above by @campbell_st

anonymous · Answer

Refer to the Mathematica plots and solutions, that are attached.