How can you tell when a quadratic equation has two identical, rational solutions?. a:when the radicand is negative. b:when the radicand is not a perfect square. c:when b in the quadratic formula is greater than the radicand. d:when the radicand equals zero

Verified Answer :

"When the radicand equals zero" is the one among the following choices given in the question that you can tell when a quadratic equation has two identical, rational solutions. The correct option among all the options that are given in the question is the fourth option or option "d". I hope the answer has helped you.

Answer:

The  quadratic equation has two identical, rational solutions:

d:      when the radicand equals zero.

Step-by-step explanation:

We know that the general quadratic equation of the type:

\(ax^2+bx+c=0\)

The solution is given by:

\(x=\dfrac{-b\pm \sqrt{D}}{2a}\)

with discriminant:

\(D=b^2-4ac\)

has:

  • Two rational and identical solution if the radicand i.e. \(D\) is equal to zero.
  • Two rational and unequal solution if the radicand i.e. D is strictly greater than zero.
  • Two imaginary solution if the radicand i.e. D is strictly less than zero.