Question 1142910
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<pre>
It is very well known fact that among all rectangles with the given perimeter the maximum area has a square 
whose side is one forth of the given perimeter.


In this problem, one forth of the perimeter is  {{{24/4}}} = 6 cm.


Therefore, the maximum possible area is  6*6 = 36 cm^2.


Any area below or equal this value is achievable.


Any area above this value is not achievable.



So, the area 40 cm^2 (case A) is not achievable.   It is your <U>ANSWER</U>.


Any area below or equal to 36 cm^ is achievable.
</pre>

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&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/quadratic/lessons/A-rectangle-with-the-given-perimeter-which-has-the-maximal-area-is-a-square.lesson>A rectangle with a given perimeter which has the maximal area is a square</A>

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