SOLUTION: Find the equation of the hyperbola (in standard and general forms) which satisfies the conditions given. Foci at (2-√13,3) and (2+√13,3), vertices at (5,3) and (-1,3)

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: Find the equation of the hyperbola (in standard and general forms) which satisfies the conditions given. Foci at (2-√13,3) and (2+√13,3), vertices at (5,3) and (-1,3)      Log On


   



Question 1167417: Find the equation of the hyperbola (in standard and general forms) which satisfies the conditions given.
Foci at (2-√13,3) and (2+√13,3), vertices at (5,3) and (-1,3)

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
Instead of doing your problem for you, I'm doing one which is EXACTLY
STEP-BY-STEP like yours.  All you have to do is use it as a model and
follow it step-by-step.  Here's the problem that I'll solve for you: 
Find the equation of the hyperbola (in standard and general forms) which
satisfies the conditions given.
Foci at (4-√41,5) and (4+√41,5), vertices at (9,5) and (-1,5)



We plot the center and foci to see whether the hyperbola is like 
this ) ( or like this: 



The hyperbola is like this ") (",so its equation is of this form:

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

where (h,k) = the center = (4,5), 
and "a" = the distance from the center to the vertex, which is the
distance from (4,5) to (9,5) which is 9-4=5

so we have this much of the 
equation:

%28x-2%29%5E2%2F5%5E2-%28y-3%29%5E2%2Fb%5E2=1

The distance from the center to either focus is the value c,
and that is the distance from (4,5) to (4+√41,5), which is 
(4+√41)-(4) = √41
and the Pythagorean relationship for all hyperbolas is

c2=a2+b2.  

%28sqrt%2841%29%29%5E2=%285%29%5E2%2Bb%5E2
41=25%2Bb%5E2
16=b%5E2
4=b

%28x-4%29%5E2%2F5%5E2-%28y-5%29%5E2%2F4%5E2=1  <---that's the standard form.

That's the standard form equation. To draw the graph, we make a defining
rectangle which is 2a=10 units wide and 2b=8 units high, with the center (4,5)
as the center of the defining rectangle, and draw its extended diagonals,
which are the asymptotes.



Now we can sketch in the hyperbola:



To get the general form we start with the standard form:

%28x-4%29%5E2%2F5%5E2-%28y-5%29%5E2%2F4%5E2=1

%28x-4%29%5E2%2F25%5E%22%22-%28y-5%29%5E2%2F16%5E%22%22=1

We multiply through by the LCD = (25)(16) = 400



16%28x-4%29%5E2-25%28y-5%29%5E2=400

16%28x-4%29%28x-4%29-25%28y-5%29%28y-5%29=400

16%28x%5E2-4x-4x%2B16%29-25%28y%5E2-5y-5y%2B25%29=400

16%28x%5E2-8x%2B16%29-25%28y%5E2-10y%2B25%29=400

16x%5E2-128x%2B256-25y%5E2%2B250y-625=400

16x%5E2-25y%5E2-128x%2B250y-369=400

16x%5E2-25y%5E2-128x%2B250y-769=0  <--that's the general form.

Now go do yours the exact same way, step by step.

You weren't asked to draw the graph, but it helps.

Edwin