(a) c = 13(4x+y+4x+y) + 5(3y)
= 112x+41y
(c) xy=9, so y=9/x, and
c(x) = 112x + 369/x
now find x where dc/dx = 0
A dog kennel with four pens is to be constructed. The pens will be surrounded by rectangular fence that costs $13 per meter. The rectangle is partioned into four pens of equal size with three partitions made of fence that costs $5 per meter. Each pen measures x meters wide by y meters long.
a) What is the total cost of the fence?
b)Suppose each pen must have 9 square meters of area. What should x and y be to minimize the cost of the fence?
1 answer
1 answer