Find the area of each circle shown below. Also please tell me how to do it, and no false info please:)
The image shows a) a circle with the diameter of 20 cm and b) a circle with the radius of 7 m.
https://www.khanacademy.org/math/basic-geo/basic-geo-area-and-perimeter/area-circumference-circle/e/area_of_a_circle
Thank You!
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To find the area of a circle, you can use the formula A = πr^2, where A represents the area and r represents the radius of the circle.
a) Let's calculate the area of the circle with a diameter of 20 cm.
First, we need to find the radius of the circle, which is half of the diameter. So, the radius (r) would be 20 cm / 2 = 10 cm.
Now, we can substitute the value of the radius (r = 10 cm) into the area formula:
A = πr^2
A = π(10 cm)^2
To calculate the area, we need to use the value of π (pi). Pi is an irrational number approximately equal to 3.14159. For simplicity, we can round it to 3.14.
A ≈ 3.14 * (10 cm)^2
A ≈ 3.14 * 100 cm^2
A ≈ 314 cm^2
Therefore, the area of the circle with a diameter of 20 cm is approximately 314 cm^2.
b) Now, let's find the area of the circle with a radius of 7 m.
We already have the value of the radius (r = 7 m), so we can substitute it into the area formula:
A = πr^2
A = π(7 m)^2
Again, using the value of π as approximately 3.14, let's calculate the area:
A ≈ 3.14 * (7 m)^2
A ≈ 3.14 * 49 m^2
A ≈ 153.86 m^2
Therefore, the area of the circle with a radius of 7 m is approximately 153.86 m^2.