I believe your mistake is that you are trying to use the sector area formula ti find arc length when there is already a formula for it.
The formula for it is

So first substitute the values in and then simplify!

Now simplify!
21 × 118 is 2478 so it's

When divided ou and multiplied, this is 21.62cm!
Because the line makes equal angle at all the points..
Answer:
I don't know that is hard
Step-by-step explanation:
You said this was an easy math question.
It's called a perpendicular line
Answer:
n = 8
Step-by-step explanation:
-7n² = -448
=> n² = -448 / -7
=> n² = 64
=> n = 
=> n = 8
Hope it helps :)
Please mark my answer as the brainliest