1. what are the values of h and k in the Quadratic function y= 2x² + 20x + 47? 2. what is the vertex form of the quadratic function y=-3x²-6x-12? 3. which of the following quadratic function has -4 and 5 as the values of h and k, respectively? 4. what formula can be used to find the values of h and k given the quadratic function y= ax²+bx+c?