The focus of the parabola is
and parabola opens down.
Parabola contains
.
Standard form of the vertical parabola is
.
Where
\Vertex :
,
Focus :
,
Here
and

Substitute
and
in standard form.


and
.
Since the parabola opens down, then
.
Therefore,
.
Vertex of parabola :
.
Axis of symmetry :
,
Axis of symmetry :
,
Directrix :
.
Directrix :
.
Write the equation for the parabola in standard form using the values of
, and
.
Substitute the values of
,
, and
in standard form.

Therefore, the standard form of the equation is
.
Graph :
\Graph the vertex, focus, axis of symmetry, and directrix.
\Construct a table values to graph the general shape of the curve.
\Graph of
:

The standard form of the equation is
.
Graph of
:

.