Parabola focus at
and directrix is 
Since the directrix is
, then the parabola is horizontal.
Standard form of horizontal parabola is
.
Where
is vertex.
If
then the parabola opens to the left and
parabola opens to the right.
Directrix is
and focus at
.
Focus
= 

.
Directrix 
.
.
Substitute
in
.


.
Vertex of parabola is
.
Find the value of
.
Substitute
in
.


.
Substitute
and
in standard form.

.
The parabola equation is
.
Latus rectum is the line segment of a parabola perpendicular to axis which has both ends on the curve.
\Obtain the points define the latus rectum, let 
Then 


The two points that define latus rectum are 
Graph:
\Draw the coordinate plane.
\Plot the vertex, focus, and the two points 
Draw the directrix line.
\Connect the plotted points with smooth curve.
\The parabola equation is
.
The two points that define latus rectum are 
Graph of
:
.