Solve for A
A=\frac{13\pi r^{2}}{60}
Solve for r
r=\frac{2\sqrt{\frac{195A}{\pi }}}{13}
r=-\frac{2\sqrt{\frac{195A}{\pi }}}{13}\text{, }A\geq 0
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A=\frac{13}{60}\pi r^{2}
Reduce the fraction \frac{78}{360} to lowest terms by extracting and canceling out 6.
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