Chapter 11.4, Problem 45SPR

To determine

To find: The area of the circle whose radius is $9\text{cm}$ .

Answer to Problem 45SPR

The area of the circle is $81\pi {\text{cm}}^2$ .

Explanation of Solution

Given:

The radius is $9\text{cm}$ .

Calculation:

Consider the area of the circle is of the form,

  $A=\pi r^2$

Here, $r$ is the radius.

Then,

  $\begin{array}{c}A=\pi {\left(9\text{cm}\right)}^2\\ =81\pi {\text{cm}}^2\end{array}$