Complex simultaneous equations are in fact just normal simultaneous equations and can be solved in the usual way, by equating coefficients of one variable and eliminating, or by substitution.
To solve the complex simultaneous equations
(1)
(2)
Rearrange (1) to give
(3) and substitute this into (2) to give
Partially expanding brackets gives
Factorising with w and taking the first term on the left over to the right hand side gives
Hence
Substituting this into (3) gives