Question

How do you do this
log_8(x+6)=1-log_8(x+4)

It says -2 but i have no idea how to get there

Answer 1

\[\log_{8}(x+6)=1-\log_{8}(x+4) \]

Answer 2

how is that true, if something has the same base, then it is = meaning (x+6)=1-(
X+4)

Answer 3

if you have 3^X+2 and 9^X+2 then u can drop it to the same base and say it is x+2=2x+4

Answer 4

how can u just put them on one side, its an equality

Answer 5

yea i was pretty sure u were wrong there

Answer 6

did eveyone give up

Answer 7

\[log_8(x+6)=1-Log_8(x+4)\]
\[log_8(x+6)+Log_8(x+4)=1\]
\[Log_8(x^2+10x+24)=1\]
to the 8
\[x^2+10x+24=8\]
\[x^2+10x+16=\]
(x+2)(x+8)
x=-2,-8

Answer 8

ok well im sitting here with a mth teacher who says both of u are wrong

Answer 9

can't be -8 because that would make log of negative number
so only -2 is right answer

Answer 10

its wrong
according to him, u did not take into account the negative infront of the log and i have no idea what any of u are talking about

Answer 11

Yes imran is right.. by that your professor means you have to check the domain and see if the value in log is not negative

Answer 12

I did that after I got my numbers

Answer 13

no he says u are both wrong and both answers are wrong

Answer 14

u cant just swap sides of an equality regardless if it has the same base

Answer 15

What is that imran is wrong in <.< the answer is -2 and that is what he has got!

Answer 16

the log is NEGATIVE

Answer 17

it is not!! if you have -2=x

Answer 18

ITs not -2 im sitting next to a phd right now u wanna tell him he is wrong?

Answer 19

lol even i have phd :P jkjk

Answer 20

If a phd is sitting next to you , why are you asking for help here

Answer 21

the log is an equality u can not just swap sides, and even if u could how can u just switch signs from a negative to a postive it makes NO sense

Answer 22

lol imran :P

Answer 23

because he wont give me the answer if he would i wouldnt be here trust me i have better things to do on friday night

Answer 24

switch signs from a negative to a postive... what do u mean by that o.O

Answer 25

u just moved the =1 over and said the log is no longer negative,

Answer 26

even wolfram alpha
http://www.wolframalpha.com/input/?i=log_8%28x%2B6%29%3D1-log_8%28%28x%2B4%29%29

Answer 27

i still dont get what you want to say man!! Resubsititute the value -2 and confrim if u dun believe us <.<

Answer 28

im not saying i dont beleieve u at all, im just saying my idiot phd professor says we are all wrong, i dunno why, besides that fact that he is an idiot

Answer 29

lol show him wolfram alphas answer

Answer 30

So he agreed o.O

Answer 31

nope
awesome
now he says we are all missing something grrr i hate this guy

Answer 32

Even wolfram alpha is missing something!?

Answer 33

accroding to this crackpot

Answer 34

or else review ur question.. u might have given an incomplete question here

Answer 35

whats what i thought but i just double checked and that is exactly what is in the book

Answer 36

Well i guarantee it is right.. you see how u handle this professor.. and if he still doesnt agree he can post the reason here... according to what i know it is RIGHT

Answer 37

its driving me nuts, sigh as soon as he cracks and gives me the answer ill let u guys know