SOLUTION: find the standard equation for the hyperbola with the given characteristics: center (1, 2) one vertex (1, 18) one focus (1, -18)

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: find the standard equation for the hyperbola with the given characteristics: center (1, 2) one vertex (1, 18) one focus (1, -18)      Log On


   



Question 979286: find the standard equation for the hyperbola with the given characteristics:
center (1, 2)
one vertex (1, 18)
one focus (1, -18)

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
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

%28y-k%29%5E2%2Fa%5E2%2B%28x-h%29%5E2%2Fb%5E2=1

and since the center is (h,k) = (4,-3), we can fill in h=4 and k=-3.

%28y%2B3%29%5E2%2Fa%5E2%2B%28x-4%29%5E2%2Fb%5E2=1

From the center (4,-3) to the vertex (4,9) is 12 units, so a=12.
We fill that in:

%28y%2B3%29%5E2%2F12%5E2%2B%28x-4%29%5E2%2Fb%5E2=1

%28y%2B3%29%5E2%2F144%5E%22%22%2B%28x-4%29%5E2%2Fb%5E2=1

We just need b.  To find b we need the Pythagorean relation for
all hyperbolas, which is c%5E2=a%5E2%2Bb%5E2.

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:

c%5E2=a%5E2%2Bb%5E2
13%5E2=12%5E2%2Bb%5E2
169=144%2Bb%5E2
25=b%5E2
5=b

Answer:

%28y%2B3%29%5E2%2F144%2B%28x-4%29%5E2%2F25=1

Now use this as a model to do your problem, which is exactly like it.

Edwin