Question

with an apothem of 15 cm and a side length of 12.4 cm. ? cm²

Explanation:

Step1: Calculate the perimeter

An octagon has 8 sides. The side length \(s = 12.4\) cm.
The perimeter \(P=8s\)
\(P = 8\times12.4=99.2\) cm

Step2: Use the formula for the area of a regular polygon

The formula for the area \(A\) of a regular polygon is \(A=\frac{1}{2}aP\), where \(a\) is the apothem and \(P\) is the perimeter.
Given \(a = 15\) cm and \(P=99.2\) cm.
\(A=\frac{1}{2}\times15\times99.2\)
First, calculate \(\frac{1}{2}\times15 = 7.5\)
Then, \(A=7.5\times99.2\)
\(A = 744\)

Answer:

\(744\)