What is true about the function h(x) = x2 + 20x – 17? Check all that apply. The vertex of h is (–10, –117). The vertex form of the function is h(x) = (x + 20)2 – 17. The maximum value of the function is –17. To graph the function h, shift the graph of f(x) = x2 left 10 units and down 117 units. The axis of symmetry of function h is x = 20.