Question

Work with a partner. Find the radius of circle.

Answer 1

Find the radius of the given circle.

Given that, $A=1.44\pi in{.}^2$

Use the formula for the area of a circle.

$A=\pi r^2$ (Write the formula)

$\Rightarrow 1.44\pi =\pi r^2$ (Substitute $1.44\pi$ for A)

$\Rightarrow 1.44=r^2$ (Divide each side by $\pi$)

$\Rightarrow \frac{12\times 12}{10\times 10}=r^2$ (Rewrite $1.44as\frac{12\times 12}{10\times 10}$)

$\Rightarrow \sqrt{\frac{12\times 12}{10\times 10}}=r$ (Take the positive square root of each side)

$\Rightarrow \frac{12}{10}=r$

$\Rightarrow r=1.2$ (Simplify)

Hence, the radius of the given circle is $1.2in.$