Expressing Area of a "n-gon" in Terms Of Y=kx^2

[Jormungand]

I have a question that I seem to be stuck on.

Backround information includes: I have a pentagon inscribed in a circle. No circumference, no radius is given.
Pentagon = 5 sides which means we have 10 interior angles (10 right triangles = Pentagon)

I found the area of my Pentagon to be A=5r^2(Sin36)(Cos36)

I then found the area of a "n-gon" to be: A=nr^2(Sin360/2n)(Cos360/2n) Where n = number of sides and 2n = number of angles.

So...

My question reads:

"If y=kx^2, we say that y varies directly with the square of x where k is the variation constant. Express the result of part b in these terms."

And ofcourse the results of part b is: A=nr^2(Sin360/2n)(Cos360/2n)
n = number of sides, 2n = number of angles.

The result of the part b is the area of a "n-gon" in terms of r and n.

I am stuck on how I can take the results of part b and express it in terms of y=kx^2

If anyone can help me that would be greatly appreciated!!!

Thank you!

 

[Deleted member 4993]

I have a question that I seem to be stuck on.

Backround information includes: I have a pentagon inscribed in a circle. No circumference, no radius is given.
Pentagon = 5 sides which means we have 10 interior angles (10 right triangles = Pentagon)

I found the area of my Pentagon to be A=5r^2(Sin36)(Cos36)

I then found the area of a "n-gon" to be: A=nr^2(Sin360/2n)(Cos360/2n) Where n = number of sides and 2n = number of angles.

So...

My question reads:

"If y=kx^2, we say that y varies directly with the square of x where k is the variation constant. Express the result of part b in these terms."

And ofcourse the results of part b is: A=nr^2(Sin360/2n)(Cos360/2n)
n = number of sides, 2n = number of angles.

The result of the part b is the area of a "n-gon" in terms of r and n.

I am stuck on how I can take the results of part b and express it in terms of y=kx^2

If anyone can help me that would be greatly appreciated!!!

Thank you!

If everything is correct then

k = n * sin(180/n) * cos(180/n)

x = r, and

y = A