Chapter 11.6, Problem 2PSA

a

To determine

To calculate: The radius of circle with area $16\pi$

Answer to Problem 2PSA

The radius of circle is $4\text{ units}$ .

Explanation of Solution

Given information : Area of circle is $16\pi$ .

Formula used: Area of circle = $\pi r^2$

Calculation: As, Area of circle is $16\pi$ ,

  $\begin{array}{l}\Rightarrow \pi r^2=16\pi \\ \Rightarrow r^2=16\\ \Rightarrow r=\sqrt{16}\\ \Rightarrow r=4\end{array}$

b

To determine

To calculate: The radius of circle with area $169\pi$ .

Answer to Problem 2PSA

The radius of circle is $13\text{ units}$ .

Explanation of Solution

Given information : Area of circle is $169\pi$ .

Formula used: Area of circle = $\pi r^2$

Calculation: As, Area of circle is $169\pi$ ,

  $\begin{array}{l}\Rightarrow \pi r^2=169\pi \\ \Rightarrow r^2=169\\ \Rightarrow r=\sqrt{169}\\ \Rightarrow r=13\text{ units}\end{array}$