Question

4+5e^(-x)=9 I think there is no solution though am I right?

Answer 1

obvious solution ;)

Answer 2

subtract 4
divide by 5
rewrite in equivalent log form
change the sign

Answer 3

or as zarkon said. make an educated guess

Answer 4

\[4+5e^{-x}=9\]
\[4-4+5e^{-x}=9-4\]
\[5e^{-x}=5\]
\[\frac{5}{5}e^{-x}=\frac{5}{5}\]
\[1e^{-x}=1\]
\[e^{-x}=1\]
x=0

Answer 5

\[1e^{-x}\] priceless

Answer 6

lol

Answer 7

i was trying to be like jim

Answer 8

mavis beacon teaches typing

Answer 9

4) 4+5e^-x=9

4 + 5e^-x = 0

5e^-x = -4

5 = -4e^x

e^x = -5/4

write it as x = ln(-5/4) <--- when you put this into calculator, you will get an error

Answer: No solution

Answer 10

where did the nine go?

Answer 11

what !

4+5e^-x=9

4 + 5e^-x = 0 <--- what happen to 9?

5e^-x = -4

5 = -4e^x

e^x = -5/4

Answer 12

good ?

Answer 13

nine of one, three quarters of a dozen of the other

Answer 14

no not good

Answer 15

This is what I got when I punched it into web 2.0

Answer 16

what happen to 9?

Answer 17

how does 9=0?

Answer 18

This is why I asked the question?

Answer 19

oh so this isn't your work?

Answer 20

i don't know what web 2.0 is

Answer 21

No it is web 2.0 work not mine.

Answer 22

don't use it
its horrible if it did that

Answer 23

It is a scientific calculator on the web.

Answer 24

use wolfram alpha or geogebra

Answer 25

try this: wolfram

Answer 26

http://www.wolframalpha.com/

Answer 27

i think it also shows you the work sometimes