Question

Help. This one lost me. Solve the formula for the specified variable.
I=nE/nr+R. Solve for n

Answer 1

Is that a one on the left side of equation or an l

if it is an l this is

\[1=nE/(nr+R)\] multiply the denominator over

nrl+Rl=nE get all the terms with n on one side

nrl-nE=-Rl

factor out n

n(rl-E)=-Rl

divide

n=-Rl/(rl-E)

Answer 2

HI, the only possible answers are:
A. n = IR(Ir - E)

B. n = -R/Ir-E


C. n = IR/Ir+E


D. n = -IR/Ir-E

Answer 3

I'm sorry I reversed the sign on accident in the denominator. The answer is D. Does what I id make sense?

Answer 4

Yes, thanks for your help. I have a picture of a graph also that I am supposed to find the equation from. Do you know of any good graph calculators?

Answer 5

I use a ti-89 but anything from ti-82 on would be good. You could also get computer software for graphing

Answer 6

Can you take a look at this one: Evaluate the function for the given value of x.
f(x)=-6x^-4x-4, x=-2
I came up with f(-2)=-20. Does that look right?

Answer 7

You get \[-6(-2)^4-4(-2)-4\]

which simplifies to

\[-6(16)+8-4\] so I would check your work again

Answer 8

Possible answers are:
A) f(-2)=-36.
B) f(-2)=-17
C) f(-2)=-20
D) f(-2)=-28

Answer 9

I'm sorry, maybe I misread your equation. Could you repost it please.

Answer 10

Evaluate the function for the given value of x.
f(x)=-6x^-4x-4, x=-2
I came up with f(-2)=-20

Answer 11

I'm assuming that the ^ symbol means squared on the keyboard.

Answer 12

not necessarily squared but "to the power"

Answer 13

How do I make the little 2 above and to the right of the x

Answer 14

That's what it's supposed to be in the expression

Answer 15

^2

Answer 16

but from there you get
\[-6(4)+8-4=-24+8-4=-20\]

so you are correct

Answer 17

Ok, thanks, I did something right! If you don't mind looking at one more...
Graph the exponential function and state the domain and range. y=5(x-3). I can't copy the graphs on here, but the possible answers to the domains/ranges are:

A) Domain: (-8,8), Range: (-8,0)
B) Domain: (0,8), Range: (0,8)
C) Domain: (-8,0), Range: (-8,0)
D) Domain: (-8,8) Range: (0,8)

Answer 18

I'm not sure you copied the right equation there. The domain and range for that equation is all real numbers

Answer 19

Lol, it's really on a workbook: Graph the exponential function and state the domain and range. y=5(x-3).

Answer 20

And those I listed are the only options for an answer, besides the pics of the graphs. Wish I could figure out how to copy/paste those...

Answer 21

is it \[5^{x-3}\]?

Answer 22

That's not the way it's written, it looks just exactly like I typed it, but maybe it's supposed to be the way you wrote it?? Your way, does it have a solution to one of those I listed?

Answer 23

I picked B and it was wrong.

Answer 24

I am really unsure, sorry

Answer 25

That's ok, I really do appreciate your help. I have other's but still trying to solve on my own at the moment. I will get back on later if you happen to still be here. Thanks again.

Answer 26

okay you can message me if need be

Answer 27

I don't know how to message you. First time on this site. How do I reach you?