Would it be right for me to assume X is positive for

and get to get X =5 as an answer.

and In Media-eval times there were 10,000 people living in a city that was struck by a plague. the number of people living after 6 days was 8,500 and after 12 days 7,225.

How would you determine the event is exponential and find the number of people living after 18 days.

if i set up my chart

0-10,000

6-8,500

12-7,225

18-X

I found a common ratio of .85 with help from some one else and after that I got kind of lost. (attempted an equation which didn't work)