What is the area of sector of a circle with 0 = 216° and radius of 7 inches? Express your answer in terms of pi?

1 answer

To find the area of a sector of a circle, we can use the formula:

\[ A = \frac{\theta}{360} \times \pi r^2 \]

where \( A \) is the area of the sector, \( \theta \) is the angle in degrees, and \( r \) is the radius of the circle.

Given:

  • \( \theta = 216^\circ \)
  • \( r = 7 \) inches

Let's substitute the values into the formula:

\[ A = \frac{216}{360} \times \pi (7)^2 \]

Calculating \( (7)^2 \):

\[ (7)^2 = 49 \]

Now substituting that into the equation:

\[ A = \frac{216}{360} \times \pi \times 49 \]

Next, simplify \( \frac{216}{360} \):

\[ \frac{216}{360} = \frac{216 \div 72}{360 \div 72} = \frac{3}{5} \]

So we can rewrite the area \( A \):

\[ A = \frac{3}{5} \times \pi \times 49 \]

Now multiply:

\[ A = \frac{3 \times 49}{5} \times \pi = \frac{147}{5} \times \pi \]

Thus, the area of the sector is:

\[ \boxed{\frac{147}{5} \pi} \text{ square inches} \]