Answer:
Explanation:
a parabola is the graph of a quadratic equation, so the general equation is
If the directrix is negative, it means the graph opens down, so a is -
and c is -3
this gives us
all we need now is what is b
b is the y intercept for
to find the y intercept, we plug in 0 for x
so the y intercept is -3
so the equation is