Question

The radius of the circle is 3cm find its circumference and area

Answer 1

Area of a circle = pi x r squared
A=pi(9), about 28.27 cm
Circumference of a circle = 2 x pi x r
C=2(pi)(3), about 18.85 cm
Hope this helps

Answer 2

C = 18.84 cm

A = 28.26 cm²

Explanation:

Hi! Our task is to find the circumference & the area of the circle, given that its radius is 3 cm. So let's start with the circumference.

The formula for the circumference is:

`\large\boldsymbol{\bullet\qquad C = 2\pi r}}`

where C = circumference & r = radius.

Substitute 3 for r. I'll also use 3.14 for pi.

`\rightarrow\boldsymbol{\qquad C = 2 \cdot 3.14 \cdot 3}`

`\rightarrow\qquad\boldsymbol{C=18.84\;cm}`

`\hspace{370}\above3`

`\underline{\underline{\bigstar\qquad\textsc{Area}\qquad\bigstar}}`

The formula for the area is:

`\large\boxed{\boxed{\sf{A=\pi r^2}}}`

Once again, I'll use 3.14 for pi, and 3 for r:

`\bf{A=3.14*3^2}`

`\bf{A=3.14*9}`

`\bf{A=28.26\:cm^2}`