Find the equation of the circle with centre : `(-a , b)`and radius `sqrt(a^2-b^2)`.

Explanation

To find the equation of the circle with center at \((-a, b)\) and radius \(\sqrt{a^2 - b^2}\), we can follow these steps:

### Step 1: Write the standard form of the equation of a circle
The standard equation of a circle with center \((h, k)\) and radius \(r\) is given by:
\[ (x - h)^2 + (y - k)^2 = r^2 \]

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