quadratic

The equation is a dome shaped parabola due to the -1 coefficient of x²

   the vertex   'x' value  will be found by  -b/2a      this will also be the axis of symm

to find the ' y' value of the vertex, put the 'x' value found above and compute 'y'

    this 'y' will be the max 'y' value.......range will be  (-inf, 'y max value')

domain is  all x    (-inf,+inf)