Question 1097067
If you have your function in the form, y=ax^2+bx+c and you want to change the form so that you can read and 'see' the vertex and symmetry axis then you could use Completing The Square.


{{{f(x)=-(x^2+2x-3)}}}
term to complete the square will be  {{{(2/2)^2=1}}}.

{{{-(x^2+2x+1-1-3)}}}
{{{-(x^2+2x+1-4)}}}
{{{-((x+1)^2-4)}}}
{{{-(x+1)^2+4}}}
-
{{{highlight(f(x)=-(x+1)^2+4)}}}


This shows {{{system(a=-1,h=-1,k=4)}}}.