Question

The area of a circle is 49π cm². Its circumference is ______.

Options

• 7π cm

• 14π cm

• 21π cm

• 28π cm

Answer 1

The area of a circle is 49π cm². Its circumference is 14π cm.

Explanation:

Let the radius be r cm.

We know:

Area of a circle

Thus, we have;

πr² = 49π

⇒ r² = 49

`⇒ r = sqrt(49)`

⇒ r = 7

Now,

Circumference of the circle = 2πr

`= (2xx22/7xx7) "cm"`

= 14π cm