#### Answer

$r = + \sqrt {\frac{A}{\pi}}, -\frac{A}{\pi}$

#### Work Step by Step

$A = \pi r^2$
$\frac{A}{\pi} = r^2$
$r = + \sqrt {\frac{A}{\pi}}, -\frac{A}{\pi}$

Published by
Pearson

ISBN 10:
013421742X

ISBN 13:
978-0-13421-742-0

$r = + \sqrt {\frac{A}{\pi}}, -\frac{A}{\pi}$

$A = \pi r^2$
$\frac{A}{\pi} = r^2$
$r = + \sqrt {\frac{A}{\pi}}, -\frac{A}{\pi}$

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