** Axis of Symmetry ** - The line which divides the parabola into two symmetrical halves. In the equation for the parabola *y* = *a*(*x* - *h*) + *k*, the axis of symmetry is *x* = *h*.

** Completing the Square ** - A process by which we add and subtract a constant to create a perfect square trinomial within an equation and transform the equation of the form *y* = *ax*^{2} + *bx* + *c* into an equation of the form *y* = *a*(*x* - *h*)^{2} + *k*.

** Discriminant ** - In the quadratic equation, the expression *b*^{2} - 4*ac*. The discriminant determines the number of solutions to a quadratic equation, or the number of *x*-intercepts of a quadratic function.

** Parabola ** - The shape of the graph of

*y* = *a*(*x* - *h*)^{2} + *k*.

Graph of *y* = *x*^{2}

** Quadratic Equation ** - An equation of the form *ax*^{2} + *bx* + *c* = 0, where *a*≠ 0, and *a*, *b*, and *c* are real numbers.

** Quadratic Formula ** - Given a quadratic equation

*ax*^{2} + *bx* + *c* = 0, the solutions are given by the equation

*x* = .

** Quadratic Function ** - A function of the form *y* = *ax*^{2} + *bx* + *c*, where *a*≠ 0, and *a*, *b*, and *c* are real numbers.

** Vertex ** - In the equation *y* = *a*(*x* - *h*)^{2} + *k*, the point (*h*, *k*) -- the minimum point in a parabola that opens upward, or the maximum point in a parabola that opens downward.