$(0,-1)$ lies on the graph of a unit circle.
Work Step by Step
A unit circle is a circle with a radius of one, with a center on the origin (0,0). Therefore the point (0,-1), is found on the unit circle. Because this is a simple example, there is no need to substitute it into the equation of a circle to find whether the radius is equal to one, because 0 squared added to -1 squared is 1, the radius of the unit circle.