Hello there! Sorry for bothering/wrong section. Need help.


New member
Dec 2, 2019
Hello there! I would really appreciate if you guys could help me with this math problem I have, it's one of the online tests and I haven't been able to find the solution in my native language or in English, maybe someone could provide some clarification.

Anyway, here's the task/test I need to complete, trying to translate it from Estonian to English the best way I can.

Rectangular cottage plot with area 2312m2 , must be fenced off on three sides. Find the plot dimensions so that the length of the fence is the shortest.
The length of the fence is *blank* meters, the width is *blank* meters
So far I have understood that the area of the plot is 2312 meters squared. I have marked the area as S, so I have gotten S=2312m2. The formula for the area calculation should be S= a * b. I have set "a" as the length of the fence that should be the minimum, how should I proceed?

Thank you for your time and help, I really appreciate it and thanks in advance!! Sorry if this is in the wrong section, maybe someone can move it?


Senior Member
Mar 16, 2016
I think the "length of the fence" means the total length of the fence rather than the side length,

ie T = a+2b and you need to minimise T where T is total length..

So S = a*b = 2312 where a is side length, as you said, and b is width.

Now you can get b in terms of a, and then get T in terms of a only.

Then minimise T using calculus.