Question

1. Write the equation of the parabola with vertex (0, 0) and focus (0, -4).

a.) x = -1/16y2
b.) x = 1/16y2
c.) y = -1/16x2
d.) y = 1/16x2

2. Write the equation of the parabola with vertex (0, 0) and directrix x = 6.

a.) x = -1/24y2
b.) y = -1/24x2
c.) x = 1/24y2
d.) y = 1/24x2

I really would appreciate any help!! Thank you!!! =)

Answer 1

the vertex and focus have the same x coordinate

so the axis of symmetry is vertical

Answer 2

this means the equation will have x^2 instead of y^2

that allows us to rule out choices A and B

Answer 3

and because the focus is below the vertex, this means the parabola must open downwards

Answer 4

Thank you! =) You helped a bunch! Am I correct to say that the answer for number 2 is A?