Question 974203
Complete the square to put into standard form.  You can read everything you need from it.


{{{-2(x^2+2x-3)}}}
{{{-2(x^2+2x+1-1-3)}}}
{{{-2((x+1)^2-4)}}}
{{{-2(x+1)^2+8}}}


The vertex is a maximum value for the expression, at (-1,8).
The range is  ( -infinity, 8].
Increasing from the left until negative 1; decreasing from negative 1 to the right.
Saying in interval notation better:  Increasing on ( -infin, -1 );  decreasing on ( -1, infinity ).