Greetings.
The answer is
a = determines the shape of parabola (upward, downward, narrow or wide)
h = determines the transformation of the graph for x-axis (For example, (x+1)², the graph would move from x=0 to x=-1
k = determines the transformation of the graph for y-axis. (For example, x²+1, the graph would move from y = 0 to y = 1.