Question 420197
the formula for the circumference of a circle is equal to 2 * pi * r


pi is a constant that is equal to 3.141592654


r is the radius of the circle.


the circumference of the circle is the same as the perimeter of the circle.


use the equation to solve for r.


you get:


2 * pi * r = 50


divide both sides of the equation by 2 * pi to get:


r = 50 / (2 * pi)


this can be simplified to r = 50 / 6.283185307 which can further simplified to:


r = 7.957747155


the formula for the area of a circle is equal to pi * r^2.


that would be the shaded area inside the circle.


use the value you just got for r to find the area.


your formula is:


pi * r^2 = area of the circle.


r = 7.957747155 so we substitute in the equation for r to get:


pi * (7.957747155)^2 = area of the circle.


this can be simplified to be:


3.141592654 * 63.32573978 = 198.9436789 square units.


the perimeter is 50 units.
the radius is 7.957747155 units.
the area is 198.9436789 square units.