Second-degree equation that represents a circle: find its centre, radius or area

1. A.
   $5\pi$
2. B.
   $9\pi$
3. C.
   $25\pi$
4. D.
   $81\pi$

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1. A.
   $\left(-1, \dfrac{3}{2}\right), \dfrac{\sqrt{5}}{2}$
2. B.
   $\left(-1, -\dfrac{3}{2}\right), \dfrac{\sqrt{5}}{2}$
3. C.
   $\left(1, -\dfrac{3}{2}\right), \dfrac{\sqrt{5}}{2}$
4. D.
   $\left(1, \dfrac{3}{2}\right), \dfrac{\sqrt{5}}{2}$

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