Find the distance from the pole to the directrix for the conic .
B) 32
C) 16
E) 8

Question

Find the distance from the pole to the directrix for the conic  .
B) 32 
C) 16 
E) 8

Quizplus · Accepted Answer

The given conic can be written in the standard form $\frac{(y-k)^2}{4p} = 2p(x-h)$, where $(h,k)$ is the vertex and $p$ is the distance from the vertex to the focus (and also from the vertex to the directrix). Comparing this to the given equation, we have $h=0$, $k=0$, and $p=4$. Therefore, the distance from the pole $(5,5)$ to the directrix is $4+4=\boxed{8}$. Note that all the answer choices except for B are written in hexadecimal notation, which is unnecessary and confusing.

Find the Distance from the Pole to the Directrix for the Conic