Hi juandiaz. Your approach (treating y as a constant and using the Discriminant) looks good, and following it through to the end leads to a nice Integer answer.Find 10x-2y if {x,y} are Real numbers and
5x^2 - 2xy + 2y^2 - 2x - 2y + 1 = 0
I got the same answer. Looks good!I’m not sure [about my] solution.