Question 176177
{{{ax^2+bx+c}}} general form
:
D=Discriminant is {{{b^2-4ac}}}

if D>0 then the equation has 2 real solutions
if D<0 then the equation has 1 real solution.
if D=0 then the equation has 2 conjugate imaginary solutions. 
:
(-1)2-4(1)(7)=-30
:
so this has 2 conjugate imaginary solutions