1. The problem statement, all variables and given/known data again there is no answer provided in the book! a +bt +ct^2 = z where t is a real parameter, and a, b, c are complex numbers with b/c real 2. Relevant equations 3. The attempt at a solution b/c real indicates that b and c are pure imaginary so when you split the equation into real and imaginary parts: x = Re(a) y = Im(a) + Im(b)t + Im(c)t^2 since t is a parameter, in the complex plane, the locus of z is a straight vertical line with x = Re(a)?