Calculating the Center of A Circle



Hello,
    s: solve([(x-x0)^2+(y-y0)^2=r^2,(x-x1)^2+(y-y1)^2=r^2],[x,y]);
This is a relatively simple problem that my Mathcad can solve in less  
than a second.
Maxima takes about a minute to come up with a [ ] answer.
The others on sci.math.symbolic agree this is a bug or should be.   
This seems basic so fixing this problem may help in solving many  
similar problems.

Regards,

Peter Nachtwey