Instead of doing your exact problem, I'll do one exactly like it, given
the exact same parts.
find the standard equation for the hyperbola with the given characteristics:
center (4, -3)
one vertex (4, 9)
one focus (4, -16)
Since the vertex (4,9) is above the center (4,-3) the hyperbola
opens up and down. So its equation is
and since the center is (h,k) = (4,-3), we can fill in h=4 and k=-3.
From the center (4,-3) to the vertex (4,9) is 12 units, so a=12.
We fill that in:
We just need b. To find b we need the Pythagorean relation for
all hyperbolas, which is
.
We have a=12. We can find c because c is the distance from the center
to the focus. The distance between the center (4,-3) and the focus
(4,-16) is 13 units, so c=13. We substitute c=13 in the Pythagorean
relation:
Answer:
Now use this as a model to do your problem, which is exactly like it.
Edwin