Helppp,, how to solve this???

[Lele763839]

A farmer wants to construct a rectangular pigpen using 400 ft of fencing.
The pen will be built adjacent to an existing stone wall, so it would be the
fourth side. What dimensions should the farmer use to construct the pen
with the largest possible area?

 

[Deleted member 4993]

A farmer wants to construct a rectangular pigpen using 400 ft of fencing.
The pen will be built adjacent to an existing stone wall, so it would be the
fourth side. What dimensions should the farmer use to construct the pen
with the largest possible area?

Assume that :

the length of the rectangle along the wall = W

the length of the rectangle perpendicular to the wall = P

So:

W + P * 2 = 400...,.......................(1)

Area = A = P * W = (400 - 2P) * P ...…...............(2)

Continue..,.

 

[Deleted member 4993]

Assume that :

the length of the rectangle along the wall = W

the length of the rectangle perpendicular to the wall = P

So:

W + P * 2 = 400...,.......................(1)

Area = A = P * W = (400 - 2P) * P ...…...............(2)

Continue..,.

What condition/s must be satisfied to maximise A(rea)?

 

[Steven G]

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