how do i find the vertex: (-8,5) Point: (2,1) i forgot :/

find the? o_O

oh how do i find the directirx sorry

hmmm what's the (2,1)? the focus point, or just a point in the parabola?

it is the focus point i believe

well.. draw both, the vertex and given focus point notice the distance between both the directrix is EXACTLY the same distance from the vertex just in the opposite direction|dw:1412808264398:dw|

oh yeah! i got that but their is a mathematical way to solve this and i can show you what my math teacher did. I am confused with some of his work

oh and i think i got this question could i ask you another one similar to this one?

hmm something tells me that's not the focus point btw

the problem is vertex: (\[(-2,8)\] Focus: \[(-2, \frac{ 81 }{ 10})\]

that is his work

i don't see how he got that for the directrix

well... let's take a close look at the vertex and focus point|dw:1412809003817:dw|

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