The quadratic formula,
, is the
solution of the general quadratic equation:
The portion of the quadratic formula under the radical sign is called the
discriminant because that value can tell you the types of roots that are in
the solution set for the quadratic.
In your example:
, a = 1, b = 4, and c = 4, therefore the
discriminant, d, is:
I'll let you finish the arithmetic.