Vertex Form of Equation for Parabolas: Determining location of Vertex, sketching the graph of a parabola , and identifying number of solutions using the Vertex form of a Quadratic function. Effects of a, h, and k. arious practice problems from text. During today's Skills session, Aiden benefited significantly from the extra practice problems involving the Vertex Form of Quadratic functions which are used to graph various parabolas.