A wall is to be constructed around a rectangle of 240 square yards with a fence running the length. The construction cost for the fence is $5 per yard and for the wall $8 per yard.
a.) Determine the model cost of the total project as a function of the length x of the fence.

Question

A wall is to be constructed around a rectangle of 240 square yards with a fence running the length. The construction cost for the fence is $5 per yard and for the wall $8 per yard.
a.) Determine the model cost of the total project as a function of the length x of the fence.

campbell_st · Answer

since area = lw  or 240 = lw  l = 240/w

if x = length then width = 240/x 

perimeter  P = 2x + 2(240/x)

                  P = 2x + 480/x

now the problem gets confusing

is the wall on all 4 sides and fence of 2

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