Question

PLEASE HELP!!!!!!

Which is an equation of a hyperbola centered at
(-1, 1) with a major vertical axis of length 4 and a horizontal axis of length 3?

A. (1/4)(x-1)^2 - (1/3)(y+1)^2 = 1
B. (1/16)(x-1)^2 - (1/9)(y+1)^2 = 1
C. (1/3)(x+1)^2 - (1/4)(y-1)^2 = 1
D. (1/9)(x+1)^2 - (1/16)(y-1)^2 = 1

Answer 1

D. (1/9)(x+1)^2 - (1/16)(y-1)^2 = 1

Answer 2

Question?

Answer 3

Yes - would you be able to explain a little about what is going on, in this problem. It's kind of confusing me. Also, why is equation D. correct? Thanks! =)

Answer 4

lets look and option A. first,

Answer 5

Do you know hyperbola standard form?

Answer 6

I'm not sure. I don't remember if I've seen/used it before.

Answer 7

Will you look it up first :)

Answer 8

Sure

Answer 9

\[\frac{1}{4}(x-1)^2 - \frac13(y+1)^2 = 1\]\[\downarrow\]\[\frac{(x-1)^2}{4} - \frac{(y+1)^2}3 = 1\] \[\frac{(x-1)^2}{4} = \frac{(y+1)^2}3 + 1\]

Answer 10

I took a look online, and I think this is it: x2/a2-y2/b2 = 1 There really wasn't too much info., on it.

Answer 11

Actually when the center (h, k) isn't at (0,0):
(x-h)^2/a2 - (y- k)^2/b2 = 1

Answer 12

the equation dosent make sense for some values of x for example x=1
in fact the equation dosent make sense for
-1<x<3

Answer 13

@UnkleRhaukus - I'm a bit confused. Is the (x-1)^2/4 = (y+1)^2/3 +1 what the formula for this particular problem would be?

Answer 14

Oh, okay. So, do you think that the problem/equations are incorrectly written?

Answer 15

i wasent sure how to find the right answer so i was going to try to understand each potential plot and then to choose the answer when we came to it

Answer 16

Oh, okay. Sure, that sounds good.

Answer 17

ok we should skip to D, because it look like it is the answer

D. (1/9)(x+1)^2 - (1/16)(y-1)^2 = 1
\[\frac19(x+1)^2 - \frac{1}{16}(y-1)^2 = 1\]
\[\frac{(x+1)^2}{9} = 1+\frac{(y-1)^2}{16} \]
if x is minus 1, the LHS is zero,
while the RHS is 1 + a positive number (n^2 is always positive)
but \[0\neq 1+n^2\]

Answer 18

Aha! I get it, now! Thank you SO much! I can't tell you how much I appreciate this!