SOLUTION: Here is the second problem that I was talking about in another submitted question. A friend of mine thinks that the answer that we found to this question is wrong, but if it is th

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: Here is the second problem that I was talking about in another submitted question. A friend of mine thinks that the answer that we found to this question is wrong, but if it is th      Log On


   



Question 9378: Here is the second problem that I was talking about in another submitted question. A friend of mine thinks that the answer that we found to this question is wrong, but if it is than I don't know how to solve it. Could you help us. It is also a elipse problem that reads-
Graph the equation and find the coordinates of the foci.
(25x^2)-(144Y^2)= 3600
I think that there might be a mistake in this problem, but what do I know? That's why I'm asking you.

Found 2 solutions by rapaljer, mathmaven53:
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
The mistake is that the equation has a DIFFERENCE of squares, which makes this equation a HYPERBOLA that opens right and left. If it is indeed an ELLIPSE, then it must be a SUM of 25x%5E2+%2B+144y%5E2+=+3600. We would need to know which one is correct to continue.

R^2 at SCC

Answer by mathmaven53(29) About Me  (Show Source):
You can put this solution on YOUR website!
25x^2 - 144y^2 = 3600
Divide both sides by 3600 and simplify
x^2/144 - y^2/25 = 1
This is the equation of a hyperbola.
In general x^/a^2 - y^2/b^2 = 1 is the equation of a hyperbola for nonzero a and b
In its derivation the quantity b^2 = c^2 - a^2 where c is the x coordinate of a focus.
We have a^2 = 144 and b^2 = 25
So c^2 = a^2 + b^2
= 169
So the hyperbola x^2/144 - y^2/25 = 1 has foci at (-c,0) and (c,0)
In other words foci at (-13,0) and (13,0)