Me !

with a vertical directix, the axis of symmetry would be:
select one:
a. perpendicular to the directix
b. parallel to the directix
c. an equation where y = k
d. only a and c

The answer would be A.
If the directix is the line on the left, and the parabola is the 'curve' on the right,
the line of symmetry would be perpendicular to the directix.

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so the line of symmetry would be about

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