this is not an algebraic equation, since it has abs.
try solving with + and with - sign separately. Also you might find you
can
solve ( ...., [z,c]);
> -----Original Message-----
> From: maxima-bounces at math.utexas.edu
> [mailto:maxima-bounces at math.utexas.edu] On Behalf Of Adam Majewski
> Sent: Monday, August 11, 2008 2:45 PM
> To: maxima at math.utexas.edu
> Subject: system of equations
>
> I'm trying to solve system of equations for c:
>
> z=z^4+2*c*z^2+c^2+c
> abs(4*z^3+4*c*z)=%e^%i
>