Does the problem say rectangular area? If so,
You're area should just be xy, if you draw a picture you will see this, you need the 2 in there when considering cost, as you have done
A farmer wishes to fence an area next to his barn. He needs a wire fence that costs $1 per linear foot in front of the barn and and wooden fencing that costs $2 per foot on the other sides.
Find x and y so that he can enclose the maximum area if his budget for materials is $4400.
Y is supposed to be .
So either my area function or my constraint is wrong?