How can you tell when a quadratic equation has two identical, rational solutions?
A) when the radicand is negative
B) when b in the quadratic formula is greater than the radicand
C) when the radicand equals zero
D) when the radicand is not a perfect square

Question

How can you tell when a quadratic equation has two identical, rational solutions? 
 A) when the radicand is negative 
 B) when b in the quadratic formula is greater than the radicand 
 C) when the radicand equals zero  
 D) when the radicand is not a perfect square

anonymous · Answer

This is a definitions thing you should memorize: :-) http://en.wikipedia.org/wiki/Discriminant#Quadratic

anonymous · Answer

okay

anonymous · Answer

FYI, "multiplicity" means it's a repeated root, in this case a double-root.  Think of it as being cloned or whatever, multiple identical solutions.

lgbasallote · Answer

hint there are two identical roots when $$b^2 - 4ac = 0$$ from the quadratic formula

does that help?

anonymous · Answer

yeah thanks