find the area and circumference of a circle of radius 28
MathBot Answer:
The area of a circle is $784 \pi \approx 2463.01\, \text{units}^2$.
The circumference of a circle is $56 \pi \approx 175.93\, \text{units}$.
Note: Approximate solutions are rounded to the nearest hundredths place.
Given: $$\begin{aligned}r&=28\end{aligned}$$
Area
The area of a circle is given by the equation: $$\begin{aligned}A&=\pi r^{2}\end{aligned}$$ where $A$ is area and $r$ is radius.
Solution:$$\begin{aligned}A&=\pi r^{2}\\A&=\pi \left(28\right)^{2}\\A&=784 \pi\end{aligned}$$
Circumference
The circumference of a circle is given by the equation: $$\begin{aligned}C&=2 \pi r\end{aligned}$$ where $C$ is circumference and $r$ is radius.
Solution:$$\begin{aligned}C&=2 \pi r\\C&=2 \pi \left(28\right)\\C&=56 \pi\end{aligned}$$
A circle is a two dimensional figure that has no corners or edges. Its radius r is the distance between the center of the circle and any point on the circle. Its diameter d is twice the radius, forming a line segment passing through the center of the circle.
The circumference C, also known as perimeter P, of a circle is the distance around a circle. $$\begin{aligned} C &= 2 \pi r \\ &= \pi d \end{aligned}$$
The area A of a circle is the region enclosed inside it. $$A = \pi r^{2}$$