You can
put this solution on YOUR website!
is called the discriminant of the quadratic equation,

. Note that this is the expression under the radical in the quadratic equation.

is the symbol for the discriminant, so
If

then there is a single root to the quadratic with multiplicity of 2 and that root is

. The term multiplicity of 2 arises from the fact that every quadratic can be represented as two factors:

where

and

can be either complex or real numbers. In the case of

,

.
If

then there are two distinct real number roots.
If

then there is a conjugate pair of complex roots of the form

where

is the imaginary number defined by