Help with quadratic graph

Introduction for linear and quadratic graphs:

A linear equation is an algebraic equation in which each term is either a constant or the product of a constant and (the first power of) a single variable.

The graph of a quadratic function is a parabola whose major axis is parallel to the y-axis. The expression ax² + bx + c in the definition of a quadratic function is a polynomial of degree 2 or second order, or a 2nd degree polynomial, because the highest exponent of x is 2.I. This could also help us on delta symbol

f the quadratic functions is set equals to zero, then the result is a quadratic equation.