Question

find the circumference and area of the circle. express answers in terms of π and then round to the nearest tenth.
find the circumference in terms of π
c = 18π cm (type an exact answer in terms of π.)
find the circumference rounded to the nearest tenth.
c = 56.5 cm
find the area in terms of π
a = 81π cm² (type an exact answer in terms of π.)
find the area rounded to the nearest tenth.
a =

Explanation:

Step1: Calcular el área en términos de π

La fórmula para el área de un círculo es \( A=\pi r^{2} \), donde \( r = 9\) cm.
Sustituyendo \( r = 9\) en la fórmula: \( A=\pi\times9^{2}=81\pi\) \(cm^{2}\)

Step2: Redondear el área al décimo más cercano

Tomar \( \pi\approx3.14159\).
Calcular \( A = 81\times3.14159\).
\(81\times3.14159 = 254.46879\)
Redondear \( 254.46879\) al décimo más cercano: \( 254.5\)

Answer:

\(254.5\) \(cm^{2}\)