Question

The area of a regular octagon is 35 cm2. What is the area of a regular octagon with sides five times as long?

A. 625 cm2

B. 875 cm2

C. 175 cm2

D. 245 cm2

Answer 1

Do you have the formulas for Area of a Polygon already?

Answer 2

no i dont ! could you tell me the area

Answer 3

\[A = \frac{Pa}{2}\]

Answer 4

what is PA? what would i put there?

Answer 5

Hint: Area of similar polygons are proportional to the square of the linear dimensions (such as a side).
A polygon with a side 5 times as long has an area of 5^2=25 times the smaller polygon.

Answer 6

^What he said

Answer 7

so it would be B , 875 ?

Answer 8

Sounds good to me. :)

Answer 9

I was just about to show her the long hard way of doing it.

Answer 10

Nice intercept @mathmate

Answer 11

thank you both !!

Answer 12

Sorry @Hero for butting in. I think the question was on the proportionality of figures.

Answer 13

yw! :)

Answer 14

It was on Area of a Regular Polygon as well

Answer 15

It would definitely been beneficial to learn how to calculate the apothem and the length of the side given the area and number of sides. It would be a little long though.

Answer 16

Yes, I know. I just said that it was the long way. Good job on saving time.

Answer 17

Sorry pal for this time. Hope that won't happen again! :)

Answer 18

Okay bro