Answer:
In a quadratic equation
a*x^2 + b*x + c = 0
the discriminant is:
b^2 - 4*a*c
if the discriminant is zero, we have the next things:
None of the constants can be equal to zero (or all of them must be equal to zero)
The discriminant tells us information about the roots of the quadratic equation, particularly, when the discriminant is equal to zero, we have that both of the roots are equal, this is because the equation for the roots is:
where each solution takes one of the two possible signs of the square root, if the determinant is zero, we do not have the term inside the square root, so both roots are equal to -b/2a