5b. What is the area for the same circle? How did you calculate it?

A = πr2


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(2 points)

1 answer

To calculate the area of a circle, you can use the formula:

\[ A = \pi r^2 \]

Where:

  • \( A \) is the area of the circle,
  • \( \pi \) (approximately 3.14 or \(\frac{22}{7}\)) is a constant,
  • \( r \) is the radius of the circle.

Step-by-Step Calculation

  1. Identify the radius: First, you need to know the radius (\(r\)) of the circle. Let's assume, for this example, that the radius of the circle is 5 units.

  2. Square the radius: Calculate \(r^2\). \[ r^2 = 5^2 = 25 \]

  3. Multiply by \(\pi\): Now, substitute \(r^2\) into the area formula. \[ A = \pi \times 25 \]

  4. Calculate the area: Using \( \pi \approx 3.14\) for calculation. \[ A \approx 3.14 \times 25 = 78.5 \]

Hence, the area of the circle is approximately \(78.5\) square units.

Final Answer

\[ A \approx 78.5 , \text{square units} \]

Make sure to replace the radius used in this example with the actual radius you have if it differs from 5 units. If you have a specific radius in mind, just follow the same steps using that value.