In your first post of this type, I provided this general procedure (and I also solved the particular problem). If you have questions on how to apply this to each different problem, you can post a comment.
The general form of a parabola:
Opening left or right: y2 = 4ax (Opening left: -4ax)
Opening up or down: x2 = 4ay (Opening down: -4ay)
To remember which is which: If it opens up or down, then there are 2 x values for every y value--similar logic for right and left.
If the vertex is not at the origin, then we apply offsets: If the origin is at (j, k), then replace x with x - k, and replace y with y = k
a is the distance from the vertex to either the focus or directrix. (2a is the distance from focus to directrix)
- Put the equation into the form described above
- Find a and use that to determine the relative location of focus, vertex, and directrix
- PLOT the function to verify your results