We know that area of the square is 141 square feet. Therefore, we can figure out the dimension of square using formula for area as shown below:
[tex]Area=a^{2}\\141=a^{2}\\a=\sqrt{141}=11.874[/tex]
We know that fencing is used along the sides of the square. Therefore, amount of fencing required will be equal to perimeter of square.
Hence, we can write:
[tex]\text{Amount of fencing}=\text{Perimeter of square}[/tex]
[tex]\text{Amount of fencing}=4a=4(11.874)=47.496[/tex]
Upon rounding to nearest foot, we get the amount of fencing required as 48 feet.