Question

What are the vertex, focus, and directrix of the parabola with the given equation?

x2 – 8x – 28y – 124 = 0

Answer 1

draw a graph and you will get every answer easily

Answer 2

Here are the choices
A. vertex (4, 5); focus (4, 2); directrix y = 2
B. vertex (–4, 5); focus (0, 7); directrix y = 7
C. vertex (4, –5); focus (4, 2); directrix y = –12
D. vertex (–4, –5); focus (4, –12); directrix y = 2

I picked B but I'm not sure if I got the right .

Answer 3

Is that right?

Answer 4

ok heres the graph http://www.wolframalpha.com/input/?i=graph+x%5E2+%E2%80%93+8x+%E2%80%93+28y+%E2%80%93+124+%3D+0

Answer 5

So it is B! I got it right, right?

Answer 6

yep