Question

find the area.
13 cm
a =? cm²
a = πr²
use π = 3.14

Explanation:

Step1: Substitute the radius into the formula

Given the formula for the area of a circle \(A = \pi r^{2}\) and \(r = 13\) cm, \(\pi=3.14\).
Substitute \(r = 13\) into the formula: \(A=3.14\times13^{2}\).

Step2: Calculate \(13^{2}\)

\(13^{2}=13\times13 = 169\).
So the formula becomes \(A = 3.14\times169\).

Step3: Multiply to find the area

\(3.14\times169=(3 + 0.14)\times169=3\times169+0.14\times169\)
\(3\times169 = 507\), \(0.14\times169 = 23.66\)
\(A=507+23.66=530.66\)

Answer:

\(530.66\)