Answer
No solutions: $a$ and $c$ have the same sign
One solution: $c = 0$
Two solutions: $a$ and $c$ have opposite signs
Work Step by Step
These are examples of formulas with the specified number of solutions.
No solutions: $x^2+1=0$
One solution: $4x^2 = 0$
Two solutions: $x^2-16=0$
