solveSystem(List) -- solve a square system of polynomial equations

i1 : R = CC[x,y];

i2 : F = {x^2+y^2-1, x*y};

i3 : solveSystem F / first                                
-- warning: experimental computation over inexact field begun
--          results not reliable (one warning given per session)

o3 = {{2.18758e-17+3.25585e-17*ii, -1}, {-1, 6.64751e-13+2.78646e-12*ii}, {1,
     ------------------------------------------------------------------------
     -6.64748e-13-2.78645e-12*ii}, {-2.10169e-17+7.62244e-18*ii, 1}}

o3 : List