Answers

2016-06-14T17:28:38+08:00
We can safely assume that the given wall is a rectangular shape. :)

Area _{rectangle} = length * width

We can represent the width as w, and length as l.
      Since length is 12 more than its width, length = w+12

Since Area < 50,
       length * width < 50
          w (w + 12) < 50
           w² + 12w < 50
         w² +12w - 50 <0
            (w + 6)² < 86
             w + 6 < 9.27 
           w + 12 < 15.27
               l < 15.27

Therefore, the length can be any value between 0 and 15.27 (estimate).
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