Consider the quadratic equation ax^2 + bx + c = 0 with a, b, c integers from -4 to 4 and a is not 0. The solutions to this equation are in the form \(x = {P \pm \sqrt D \over Q}\) where D is square free . Determine the largest possible value of D.
You get the largest D when you take a = -4, b = 4, and c = 4. This gives you D = 80.