Sergio wants to fence in a circular portion of a backyard for a play space for his dog determine the area of the largest portion of the yard Sergio can enclose with 72 feet of fencing

1 answer

To determine the area of the largest circular portion of the yard that Sergio can enclose with 72 feet of fencing, we start by recognizing that the circumference \( C \) of a circle is given by the formula:

\[ C = 2\pi r \]

where \( r \) is the radius of the circle. Sergio has 72 feet of fencing to use as the circumference, so we set up the equation:

\[ 2\pi r = 72 \]

Now we can solve for \( r \):

\[ r = \frac{72}{2\pi} = \frac{36}{\pi} \]

Next, we can find the area \( A \) of the circular play space using the formula for the area of a circle:

\[ A = \pi r^2 \]

Substituting the value of \( r \):

\[ A = \pi \left(\frac{36}{\pi}\right)^2 \] \[ A = \pi \left(\frac{1296}{\pi^2}\right) \] \[ A = \frac{1296}{\pi} \]

Now, calculating this numerically, using \(\pi \approx 3.14\):

\[ A \approx \frac{1296}{3.14} \approx 412.68 \text{ square feet} \]

Thus, the area of the largest portion of the yard that Sergio can enclose is approximately 412.68 square feet.