Observe the graph :
\The graph of the poarabola is vertically opens upward ,so the general form of the parabola equation is
.
From the graph the vertex of the parabola is
.
Substitute
in
.


The parabola opens upward .so the value of
is positive.
Consider the point
on the parabola.
Substitute
in
.


.
Substitute
in
.


Therefore, the equation of the parabola is
.
The equation of the parabola is
.
The focus of the parabola is
.
Substitute
and
.

The focus of the parabola is
.
The directrix of the parabola is
.
Substitute
and
.


The directrix of the parabola is
.
The equation of the parabola is
.
The focus of the parabola is
.
The directrix of the parabola is
.