Simple code made to solve easy expressions using quadratic formula and view graph.
Vertex, roots, extra points and Y axe are now shown.
Leave 1 if no coefficient. Works only with int numbers. Red dot is vertex, green dots are roots, half-opaque black dots are extra points for easy building a parabola on a sheet of paper.
- when expression is incorrect (doesn't have roots)
- when there is one root
- when there are two roots
