The quadratic function is
.
Rewrite the quadratic function 
Compare the above quadratic function with
, then
. \ \
The vertex of the function is
and axis symmetry is
.
Since
, the graph opens down and has the same shape as the graph of
,
but it is translated 3 units up.
The vertex of the quadratic function is
, axis symmetry is
and
the graph opens down and translated 3 units up. \ \