Answer:
Explanation:
The area for the sector of a circle is
where theta is the measure of the central angle. We have some given values to fill in:
Area is 64π and the central angle is 90°, so all we have left to find is the radius. Filling into the equation:
![64\pi =(90)/(360)*\pi r^2](https://img.qammunity.org/2022/formulas/mathematics/college/y9csfz9j7lxw9yxi6f2g7z0o9b3mjwa4yl.png)
Let's get that solved for r-squared first:
Doing all the math on that gives us:
![256=r^2](https://img.qammunity.org/2022/formulas/mathematics/college/axbhl2o75v7jlc2jc26w3rbj4k9tyd3uf1.png)
Take the square root of both sides and get that r = ±16. BUT we know that lengths cannot be negative, so we disregard the -16 and say that the radius is 16 inches.