Answer
$0.44\text{ rad}.$
Work Step by Step
Here, $r$ denotes the radius of the sector of the circle.
The Area of sector can be computed by the formula:
$A=\frac{\theta}{2}\cdot r^2$
where $\theta$ is the central angle measure in radians.
Hence here we have $8=\frac{\theta}{2}\cdot 6^2\\\left(\frac{2}{36}\right)8=\left(\frac{2}{36}\right)\frac{\theta}{2}\cdot 6^2\\\frac{4}{9}=\theta.$
Thus, $\theta\approx0.44\text{ rad}.$
