Question

If we know r, the radius of a circle, we can find its area, A, by using the rule πr
2
.
Now, use your equation to find the approximate area of the circle. What is 3.14 · 12
2
?
r
Input Output Arrow
πr
2

Input Output Arrow
A


A = πr
2

A = π(12)
2

A ≈ 3.14 · (12)
2

A ≈

37.68
1,419.78
452.16
75.36

Answer 1

To find the area \( A \) of a circle with radius \( r = 12 \) using the formula \( A = \pi r^2 \), we can proceed with the following calculation:

1. Substitute the value of \( r \) into the equation:
\[
A = \pi(12)^2
\]

2. Calculate \( (12)^2 \):
\[
(12)^2 = 144
\]

3. Now plug this value into the equation:
\[
A = \pi \cdot 144
\]

4. Using \( \pi \approx 3.14 \):
\[
A \approx 3.14 \cdot 144
\]

5. Multiply \( 3.14 \) by \( 144 \):
\[
A \approx 452.16
\]

Therefore, the approximate area of the circle is \( 452.16 \).