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

Question

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

jdoe0001 · Answer

find the? o_O

superhelp101 · Answer

oh how do i find the directirx sorry

jdoe0001 · Answer

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

superhelp101 · Answer

it is the focus point i believe

jdoe0001 · Answer

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|

superhelp101 · Answer

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

superhelp101 · Answer

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

jdoe0001 · Answer

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

superhelp101 · Answer

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

superhelp101 · Answer

attachment

superhelp101 · Answer

that is his work

superhelp101 · Answer

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

jdoe0001 · Answer

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