Question

Solve 5^x = 4^(x+3)

This is as far as I can get before I'm stuck:
5^x = 4^(x+3)
log 5^x = log 4^(x+3)
x log 5 =(x+3) log 4

I think I'm supposed to isolate the x's and log's, but if I do that, then I don't have an x left at all... help?

Answer 1

xlog5 = xlog4 + 3log4 okay?

Answer 2

I'm following you...

Answer 3

move the x's all on the same side, what will u get?

Answer 4

xlog5 - xlog4 = 3log4?

Answer 5

regroup n u get: x(log5-log4)=3log4 right?

Answer 6

right

Answer 7

From WolframAlpha:

Answer 8

So x= what?

Answer 9

x=-( 6 log(2) / ( 2 log(2) - log(5) ) )

Answer 10

x=18.6377?

Answer 11

Yes

Answer 12

Bingo :)

Answer 13

Thank you so much!!

Answer 14

Welcome @BethLM39 btw cute doggie :D

Answer 15

haha thanks again :)