Answer: B) 0 real roots
---------------------------------------
The general rule is...
if D > 0, then you have two different real roots (see note below)
If D = 0, then you have exactly one real root
If D < 0, then you have no real roots (the two roots are imaginary/complex)
where D is the discriminant found by the formula
D = b^2 - 4ac
Note: If D is also a perfect square, then the two real roots are also rational. This assuming that a,b,c are rational.
