Step 1:
\The focus of parabola
and directrix 
Standard form of horizontal parabola 
Where center is
, focus is
and directrix is
.
In this case 


And 
Step 2:
\Add the equations (1) and (2).
\

Substitute
in equation (2).


Step 3:
\Substitute the values
,
and
in standard form.



Solution:
\The parabola equation
.