Question

Guys, i need an instant answer. If i have a function y=(b*x-a)/(1+c*x), how can i find x when i already have y? For example, y=33.6, how much is x?

Answer 1

hmmm hold on

Answer 2

write an actual equation using the little equation button below or take a pucture of it so I know what you are doing. that way i know if i can help you or not

Answer 3

I written an actual equation

Answer 4

that was an example of an actual equation.

Answer 5

\[y=\frac{(b^x-a)}{(1+c^x)}\] is it that?

Answer 6

No

Answer 7

\[y=\frac{b^{x-a}}{(1+c*x)}\]

Answer 8

\[y=\frac{(b*x-a)}{(1+c*x)}\] or that?

Answer 9

Yes

Answer 10

then you cannot solve it because you need (b) and (a). without those two solving the problem mathmatically is impossible.

Answer 11

you would have ≠ no answer.

Answer 12

i have them

Answer 13

wow. now you tell me. okay tell me what they are then.

Answer 14

B= 0,187344 and a= -3,5169955 and c= -0,014443694

Answer 15

and your y is 33.6?

Answer 16

yes

Answer 17

so \[33.6=\frac{\left(0.18734x+3.517\right)}{\left(1-0.01444x\right)}\]

Answer 18

\[\mathrm{Multiply\:both\:sides\:by\:}1-0.01444x\]

Answer 19

\[33.6\left(1-0.01444x\right)=\frac{0.18734x+3.517}{1-0.01444x}\left(1-0.01444x\right)\]so then it is \[33.6\left(1-0.01444x\right)=0.18734x+3.517\]

Answer 20

\[distribute~33.6\left(1-0.01444x\right)\]\[33.6\left(1-0.01444x\right)=0.18734x+3.517\]

\[\mathrm{Multiply\:both\:sides\:by\:}1000000\]\[33.6\cdot \:1000000-0.48518x\cdot \:1000000=0.18734x\cdot \:1000000+3.517\cdot \:1000000\]\[33600000-485184x=187340x+3517000\]

Answer 21

\[\mathrm{Subtract\:}33600000\mathrm{\:from\:both\:sides}\]\[33600000-485184x-33600000=187340x+3517000-33600000\]\[-485184x=187340x-30083000\]
\[\mathrm{Subtract\:}187340x\mathrm{\:from\:both\:sides}\]\[-485184x-187340x=187340x-30083000-187340x\]\[-672524x=-30083000\]

\[\mathrm{Divide\:both\:sides\:by\:}-672524\]\[\frac{-672524x}{-672524}=\frac{-30083000}{-672524}\]\[x=\frac{7520750}{168131}\]\[\mathrm{Show\:solutions\:in\:decimal\:form}\]\[x=44.73149\]

Answer 22

there ya go.

Answer 23

but its not correct. It has to be somewhere between 50 and 60 definetly

Answer 24

well its not. soooo

Answer 25

Looking at graph, it is 54

Answer 26

excuse me, 55

Answer 27

Could you write me a solution with just a b c and x without numbers. I would be very gratefull.

Answer 28

http://www.mathpapa.com/algebra-calculator.html look

Answer 29

you chose 33.6 dont forget that.

Answer 30

haha thank you for this website...

Answer 31

your welcome. but it was more to prove that my calculations were correct

Answer 32

But i still dont get it.

Answer 33

either you chose the wrong y, or have the wrong equation

Answer 34

for 45% i have 15, and for 33.6 i have now 44%. Its not possible

Answer 35

This equation works, as i found y to be correct with any x

Answer 36

Ill put 44 and find out y value

Answer 37

but is it? here let me do one with x and see if it is really correct

Answer 38

If you put x to be 44, the y is 12.96

Answer 39

i got y=32.25088 for x=44

Answer 40

its your equation mate :/

Answer 41

x=44 cant be 32.... i did it 5 times

Answer 42

The problem is that that site is wrong. It gives me a solution for x, but clearly it isnt

Answer 43

this is so strange

Answer 44

If i start to guess x and plug in the formula, i will eventualy get close value of y, but there just HAS to be a better way

Answer 45

my bad wrong link http://www.cymath.com/answer.php?q=y%3D(0.18734(44)%2B3.517)%2F(1-0.01444(44))

Answer 46

I tried for x=55 and i got y=33. So the formula corresponds to the graph. Everything is fine exept the equation for x

Answer 47

my bad wrong link http://www.cymath.com/answer.php?q=y%3D(0.18734(44)%2B3.517)%2F(1-0.01444(44))

Answer 48

Ok, but that link contains the equation for y, but not for x

Answer 49

oh my heck stop it. you fricking equation is wrong. when x=44 y=32 https://www.symbolab.com/solver/step-by-step/32%3D%5Cleft(0.18734%5Cleft(x%5Cright)%2B3.517%5Cright)%2F%5Cleft(1%E2%88%920.01444%5Cleft(x%5Cright)%5Cright)%20/?origin=button
http://www.cymath.com/answer.php?q=y%3D(0.18734(44)%2B3.517)%2F(1-0.01444(44)) now its done both ways. same answer

Answer 50

jsyk i rounded x and y :)

Answer 51

do you know where is wrong?

Answer 52

up to 32 and 44.


when x is 44 y is (about) 32
when y is 32 x is (about) 44

Answer 53

But ask yourself, if you get a value of y with a certain x, could you get an x with a value of y. I think the answer is YES....

Answer 54

no. i dont. im sorry. :/ i need to go eat supper too... @Zale101 @phi can you see if you can help this person please?

Answer 55

i told you they get the same answer when reversed. your confusing

Answer 56

But when i plug in x=44 for y=(b*x-a)/(1+c*x), I get 12.96

Answer 57

When i plug in x=55 in y=(b*x-a)/(1+c*x), I get 33... for y

Answer 58

a= -3,516995576918316
b= 0,18734459582847
c= -0,0144436993225714