Explanation:
Hey there!
The centre of a circle is (-1,-1) and radius is 1 unit.
From centre of a circle (h,k) and radius "r" , the equation is (x-h)²+(y-k)² = r²
Then;
(x+1)² + (y+1)² = 1²
Therefore, the equation of a circle is (X+1)² + (y+1)² = 1.
Hope it helps!