Question

What is the area of a regular octagon with a side length of 5.8 centimeters and an apothem length of 7 centimeters?
A.324.8cm
B.162.4cm
C.40.6cm
D.20.3cm

Answer 1

Let's start with what we know:
Area of regular octagon = 1/2 x perimeter x apothem

We know the apothem, so all that we need to find to fill in the above equation is the perimeter:
perimeter = 8 * 5.8 = 46.4cm

Now we can fill in our original equation and solve:
Area of regular octagon = 1/2 x perimeter x apothem
Area = 1/2 x 46.4cm x 7cm = 162.4cm^2

The answer is B. 162.4cm^2