## siddy20 2 years ago Find the circumference of 2 inches.

1. kirbykirby

Is this for a circle with radius 2 inches, or diameter 2 inches?

2. kirbykirby

Then the formula for a circumference of a circle is $\pi*d=\pi*2=2\pi$ where d = diameter, and that's just pi

3. kirbykirby

or more specifically, $2\pi$ inches to keep the units

4. siddy20

Yes there is: The formula for area is $2\pi*r^2$ where r = radius Now you need to know that diameter = 2*radius So d = 2r Since d = 2 2 = 2r r = 1 So the area is $2\pi*r^2=2\pi(1)^2=2\pi$ in inches^2 as units