To find the length of one side of a square garden with an area of 147 square feet, we can use the formula for the area of a square, which is:
\[ \text{Area} = \text{side}^2 \]
To find the length of the side, we take the square root of the area:
\[ \text{side} = \sqrt{147} \approx 12.12 \text{ feet} \]
Since 12.12 feet is closest to 12 feet, the approximate length of one of the sides is 12 feet.
Next, to calculate the perimeter of the square garden, we use the formula for the perimeter of a square, which is:
\[ \text{Perimeter} = 4 \times \text{side} \]
Using the approximate side length we found:
\[ \text{Perimeter} \approx 4 \times 12 = 48 \text{ feet} \]
Since 48 feet is closest to 49 feet, the approximate perimeter of the garden, and the amount of fencing needed, is 49 feet.