I know that the vertex of a parabola (h, k) is
assumegeneric formto the standard parabola form
by completing the square? I know that the vertex of a parabola (h, k) is
and
but I can't figure out how the first form gets to the second. I just want to know how the standard form is derived form the generic form by completing the square in a general way (meaning without numbers, just the letters to represent the constants); step-by-step please!