Question

What is the area of the regular octagon given below? If necessary, round your answer to two decimal places.

Answer 1

A = (8 x 15) (18.1)

Answer 2

You are close, but you made a small error.
There are 8 triangles as shown below.

Answer 3

The area of each triangle is
A = (1/2)bh
The area of 8 such triangles is
A = 8(1/2)bh
A = 4bh
A = 4(15)(18.1)

Answer 4

dosent that still give me the answer 1086 :/

Answer 5

This does give the answer 1086, but what you had earlier gave the answer 2172.

Answer 6

yeeah that was before dividing it by half ........so in reality either method works :/

Answer 7

No.

A = (8 x 15) (18.1) is incorrect bec you did not divide by 2, and your answer is twice what it should be.

A = 4(15)(18.1) is correct and give the right answer.

Answer 8

so i have to cross out the 1/2 by multiplying by 2 ????

Answer 9

The area of the octagon is given by:
A = 8(1/2)bh
Substitute b and h:
A = 8(1/2)(15)18.1)
Now multiply all the numbers together:
A = 4(15)(18.1)
A = 60(18.1)
A = 1086