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Answer:

No diagram and no explanation what 9 is.

However, if it is an octagon with each side equal to 9 then

area = (# of sides * side^2) / (4 * tan (180 # of sides))

area = 8 * 9 * 9 / (4* tan (180 / 8)

area = 648 / 4 * 0.41421

area = 391.1059607446

answer is C

Step-by-step explanation:

The area of the considered octagon which has distance from its center to the vertex of 9 m is given by: Option b). 229.1 m²

How to find the area of a regular octagon?

If the regular octagon has sides of 'a' units, then its area is:

[tex]A = 2(1+\sqrt{2})a^2 \: \rm unit^2[/tex]

Consider the attached figure below (second figure too).

If we find the value of 'a', then we can use the above formula.

Since there are 8 equal sides in a regular octagon, the angle from center to each of the side is full angle / 8 = 360/8 = 45 degrees.

Since the angle OA is perpendicular on BC, due to symmetry, we have the angle BOC divided into 2 parts.

Thus, we get:

m∠AOB = 45/2 degrees = 22.5°

Using the sine ratio from the perspective of angle AOB, we get:

[tex]\sin(m\angle AOB) = \dfrac{|AB|}{|OB|}\\\\\sin(22.5^\circ) = \dfrac{a/2}{9}\\\\a \approx 2 \times 9 \times 0.38268 \approx 6.888[/tex] meters

(since length of AB is half of length of BC, which is 'a' units).

Thus, we get:

[tex]A = 2(1+\sqrt{2})a^2 \approx 2(1+\sqrt{2})(6.888)^2 \approx 229.1\: \rm m^2[/tex]

Thus, the area of the considered octagon which has distance from its center to the vertex of 9 m is given by: Option b). 229.1 m²

Learn more about area of a regular octagon here:

https://brainly.com/question/858868

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