Cygnus X-1

After many differnt typs of astronomical measurements, it is now that believed that X-1 is a black hole a. Find the location of this black hole relative to earth b. Caculate Schwarzchild radius of the Cygnus X-1 black hole Help I haven't been able to find the mass of Cygnus X-1. I cannot caculate the schwarzchild radius without this information. I guess I am stumped. Been on the net and totally confused. Equation for Schwarzchild radius r=2GM/(c squared) R=radius G=Gravitational Constant M=Mass C= Speed of light