Question

The formula for the circumference of a circle is C = 2r, where r is the radius and C is the circumference. The equation solved for r is r = .

Find the radius of a circle that has a circumference of 16.

Answer 1

Answer: 8 units

Explanation:

Given: The formula for the circumference of a circle is
`C=2\pi r`, where r is the radius and C is the circumference.

To solve equation for r , we divide
`2\pi` on both sides, we get

`r=(C)/(2\pi)`

Now, the circumference of the circle =
`16\pi \text{units.}`

Then,
`r=(16\pi)/(2\pi)=8\ \text{units}`

Hence, Circumference of the circle = 8 units

Answer 2

The answer is r = C/2π; r = 8/π

C = 2πr

Divide both sides by 2π:
C/2π = 2πr/2
C/2π = r

r = C/2π
C = 16
r = 16/2π
r = 8/π