Question

Please Help!

The rational function has a y-intercept. What is the equation for this function?

Answer 1

Heres the graph! I can't figure out how to get the equation! I know how to do the reverse, use the function to get the graph! Please help!

Answer 2

*The rational function has a y-intercept of 7, I meant to say at the top

Answer 3

what does this function "look" like to you?

Answer 4

you should know what the basic functions look like

Answer 5

Anybody have any clue how to get the equation through the graph?? My textbook only shows how to use a function to find the graph... I mean what steps do i take to do it, i know what a function looks like

Answer 6

you need to identify what parent function we are working with

Answer 7

does this look like
y=x, y=x^2,y=x^3, y = 1/x, .....?

Answer 8

using general form y= (a/x-h) +k then translate?? like horizontal and vertical, the book refers to graphing rational functions like y=x^2+x-12/x^2-4. And finding graph but how do i find the equation?

Answer 9

(a/x-h) +k

Answer 10

ok so, the h is the horizontal shift of 1/x

Answer 11

which way is your graph shifted?

Answer 12

2 units to the left

Answer 13

ok so we want (a/x+2) +k

Answer 14

do you see why?

Answer 15

f(x+2) shifts left and f(x-2) shifts right, horizontal shifts are counter intuitive...

Answer 16

right, translations through the parent function

Answer 17

yes, your parent function is 1/x

Answer 18

ok so how far has it moved up?

Answer 19

stretch of 5, or is that a reflection

Answer 20

its a vertical shift of 5

Answer 21

so we have (a/x+2) +5

Answer 22

notice that horizontal shifts are counter intuitive but vertical shifts are exactly how one would expect.

Answer 23

a=7??

Are u sure the equation doesn't having something to do w/ horizontal and vertical asymptotes instead of parental functions, see this is what i mean about me confusion to writing this equation

Answer 24

a = 4

Answer 25

7 = a/2+5
about your other question. we can think of it that way as well
we see that the horizontal asymptote is at y = 5

Answer 26

not to butt in, but since there is a "vertical asymptote" at x = -3, shouldn't the denominator be x + 3 ?

Answer 27

its at -2

Answer 28

oops sorry

Answer 29

ive told you how to write the equation, you will get the same answer the other way. if you would like me to explain I will....

Answer 30

or is it parental function i am confused... @zzr0ck3r

Answer 31

yes please explain :)

Answer 32

so you have the equation a/(x-h)+k
if we let x get big we see that you will be very close to y=5
notice what happens in a/(x-h)+k if we let x get big
we get a/(huge number)+k if we let x go to infinity we get a/infinity + k, so we get 0+k
so for you k=5

now as far as h, we cant divide by 0 and this is what causes a vertical asymptote, so you look at your asymptote and see it occurs as x=-2 so if we let x=-2 then we have
a/(x+2)+5, note that if you let x = 2 then you would be dividing by 0 and thus getting a vertical asymptote.

to obtain a, you do the same thing as last time, it has nothing to do with asymptotes.

so at first I showed you how to get the answer from translations, then I showed you how to get the answer from investigating asymptotes.

both the same answer

Answer 33

Got it so the equation can be found both ways, so let me see if i got it
Would this be equation? y=4/(x+2)+5

Answer 34

correct

Answer 35

Thanks so much!!!!!

Answer 36

@satellite73 is this right can u double-check! :)

Answer 37

if you understand it you should know its right, if you don't you should ask me a question

Answer 38

No i think its right based on what i know but i struggle w/ math lol

Answer 39

im not worried about being right, im worried you dont understand it