Question

10. What is the equation of the directrix for the parabola-8(y - 3)=(x +4)2?A) y=5B) y=1C) y=-2D) y=-6

Answer 1

Step 1:

In this question, we are given the following:

The equation of the directrix for the parabola:

`-8\text{ \lparen y-3\rparen= \lparen x+ 4\rparen}^2`

Step 2:

The details of the solution are as follows:

Next, we can see that the equation of the directrix for the parabola is at:

`\text{y = 5 }`

This is because:

`\begin{gathered} y\text{ -3 = \lparen}(-1)/(8))\text{ \lparen x + 4 \rparen}^2 \\ y\text{ = \lparen-}(1)/(8))\text{ \lparen x + 4\rparen}^2+\text{ 3} \end{gathered}`

Then, y = k - p

y = 3 - p

p = 1/ 4a

p = 1 / 4(-1/8)

p = -2

y = 5