The area of a circle is 28.26 square centimeters. What is its diameter (use 3.14 for ð)?
A = pi * r^2
28.26 = 3.14 * r^2
28.26 / 3.14 = r^2
9 = r^2
3 = r
D = 2r
The ratio of the circumference of a circle to its diameter is called π. The ratio of the circumference to the diameter of a circle is 28.26 cm to 9 cm.
To find the diameter of a circle when given its area, you can use the following formula:
Area of a circle = π * (radius)^2
In this case, we are given the area as 28.26 square centimeters and asked to find the diameter. Since the formula involves the radius, we need to find the radius first, and then we can calculate the diameter.
Step 1: Find the radius:
Let's rearrange the formula for the area to solve for the radius:
Area of a circle = π * (radius)^2
(radius)^2 = Area of a circle / π
(radius)^2 = 28.26 / 3.14
Step 2: Solve for the radius:
Taking the square root of both sides to solve for the radius:
radius = √(28.26 / 3.14)
Using a calculator, evaluate the square root and divide the given area by π to find the radius.
Step 3: Calculate the diameter:
The diameter of a circle is twice the radius, so once we have the radius, we can multiply it by 2 to find the diameter.
diameter = 2 * radius
Substitute the value of the radius into the formula to find the diameter.
By following these steps, you can find the diameter of a circle when given its area.