# If the complex number $\;z=x+iy\;$ satisfies the condition $\;|z+1|=1\;$ , then z lies on

(a) x - axis(b) Circle with centre (1,0) and radius 1(c) Circle with centre (-1,0) and radius 1(d) y - axis

Explanation :
$|z+1| =1$
$|(x+1)+iy| =1$
$(x+1)^{2} + y^{2} =1^{2}$
Which is a Circle with centre (-1,0) and radius 1 .