Question

HELLLLPPPP!

Answer 1

Excuse me, but please post your question.

Answer 2

Any more to it?

Answer 3

no

Answer 4

Try this site out: http://answers.yahoo.com/question/index?qid=20110504171748AARuyBr

Answer 5

Or this one if ur still here :| http://answers.yahoo.com/question/index?qid=20130126083002AAy9oef

Answer 6

oh ok thanks!

Answer 7

@robtobey !!

Answer 8

can you please help me with the question i sent you

Answer 9

this goes with the question

Answer 10

@robtobey do you think u can help

Answer 11

A plot of the curve 1/x and 5/(x+6) is attached. The blue curve is 1/x .

Answer 12

how can i explain the way it compares though

Answer 13

im still confused

Answer 14

@robtobey ??

Answer 15

????

Answer 16

Not sure what the answer to the question should be. 1/x generates a sharper curve, and is closer to the origin than the other curve.

Answer 17

thats the way to compare them... this question is sooo hard

Answer 18

@phi !!!

Answer 19

Please help with this question
The rational function has a y-intercept of 7. What is the equation for this function?

Answer 20

@phi you think you can help

Answer 21

Please im so stuck

Answer 22

You are looking at a hyperbola. the generic equation is
\[ \frac{(x-h)^2}{a^2} - \frac{(y-k)^2}{b^2} =1\]

Answer 23

(h,k) is the point where the asymptotes intersect (-2,5)

Answer 24

so we can replace h and k in the equation with numbers
\[ \frac{(x- -2)^2}{a^2} - \frac{(y-5)^2}{b^2} =1\]
\[ \frac{(x+2)^2}{a^2} - \frac{(y-5)^2}{b^2} =1\]

Answer 25

thats the equation

Answer 26

I mean is that the answer or do keep going

Answer 27

we need to figure out a and b

Answer 28

oh ok.. how do you do that

Answer 29

@phi ?

Answer 30

how do you find a and b

Answer 31

@robtobey do you know how to find a and b

Answer 32

or @phi

Answer 33

were you typing a reply @phi

Answer 34

I will have to work it out

Answer 35

oh ok... I will wait

Answer 36

Do you have it yet?

Answer 37

@phi??

Answer 38

Ok I decided to start with
\[ (y-5) = \frac{c}{x+2} \]
where (-2,5) is the "center"
to find c, replace (x,y) with (0,7)
\[ (7-5) = \frac{c}{0+2} \]
we find c=4
and the equation is
\[ (y-5) = \frac{4}{x+2} \]

Answer 39

So do i forget about what u told me before

Answer 40

or
\[ (x+2)(y-5) = 4 \]

Answer 41

where does the (y-5)=c/(x+2) come from

Answer 42

The formulas I started with are for hyperbolas that are symmetric about the x-axis or the y-axis. But your hyperbola is rotated. It is a version of
x*y= k
there is a way to switch between the equations, but it is tricky

Answer 43

So i just start it out the way you just told me

Answer 44

So i do it this way
(y−5)=c x+2
where (-2,5) is the "center"
to find c, replace (x,y) with (0,7)
(7−5)=c 0+2
we find c=4
and the equation is
(y−5)=4 x+2
and for get the other way correct?

Answer 45

I think I would start with
(x-h)(y-k) = c^2 and you have to find h and k
as before, (h,k) is where the asymptotes meet, at (-2,5)
so we know them
we get
(x+2)(y-5)= c^2
now use (0,7) to find c^2
we get
4= c^2
(and c=2, though we don't care)
the equation is
(x+2)(y-5)= 4

Answer 46

I remembered that a hyperbola whose asymptotes are parallel to the x- and y-axes has the equation x*y= c^2
your graph is that kind of a hyperbola.

Answer 47

as a test, I see (2,6) is on the curve, so if we use this point it should work
(2+2)(6-5)= 4*1= 4 which matches c^2= 4

Answer 48

also, (-6,4) is on the lower curve
(-6+2)(4-5)= -4*-1= +4 which is (again) c^2= 4
so it looks like the correct equation

Answer 49

ok ?

Answer 50

Yeah that makes perfect sense!

Answer 51

Thaks sooo mUch @phi!