Question

find the circumference and area of this figure.
c = ? units
a = units²
use π = 3.14
round your answer to the nearest hundredth

Explanation:

Step1: Find the radius

The distance between the two points (1,5) and (8,5) is the diameter. Using the distance formula \(d=\vert x_2 - x_1\vert\) (since \(y_1=y_2 = 5\)), \(d=\vert8 - 1\vert=7\). The radius \(r=\frac{d}{2}=\frac{7}{2}=3.5\)

Step2: Calculate the circumference

The formula for the circumference of a circle is \(C = 2\pi r\). Substitute \(r = 3.5\) and \(\pi=3.14\).
\(C=2\times3.14\times3.5\)
\(C = 6.28\times3.5\)
\(C=21.98\)

Step3: Calculate the area

The formula for the area of a circle is \(A=\pi r^{2}\). Substitute \(r = 3.5\) and \(\pi = 3.14\).
\(A=3.14\times(3.5)^{2}\)
\(A=3.14\times12.25\)
\(A = 38.465\approx38.47\)

Answer:

\(C = 21.98\) units, \(A=38.47\) units²