If you have a quadratic of the form then its solutions are
I'll leave you to do the research why this is so - hint, you complete the square.
Can you see that the solution depends on stuff under a square root? This is called the discriminant, and is denoted by .
If there are exactly two solutions. (Why?)
If there is exactly one solution. (Why?)
If there are not any solutions. (Why?)
Can you see what a, b and c are in this equation? Find the discriminant and tell me what you can determine about the solutions.