Question

In which of the following circles are the values of the area and circumference the same? Approximate Π as 3.14.

a circle with a radius of 2 feet
a circle with a diameter of 2 feet
a circle with a radius of 4 feet
a circle with a diameter of 1 foot

Answer 1

Circle with a radius of 2 feet

Explanation:

Answer 2

We know that:


`A = \pi r^2`

and


`C=2\pi r`

so:


`A=C\\\\\pi r^2=2\pi r\qquad|:\pi\\\\r^2=2r\qquad|:r\\\\\boxed{r=2}`

It is true when radius = 2 units, so correct answer is:

A) a circle with a radius of 2 feet.