The half life of a certain substance is about 4 hours. the graph shows the decay of a 50 gram sample of the substance that is measured every hour for 9 hours.

a graph shows time (hours) labeled 1 to 10 on the horizontal axis and quantity (grams) on the vertical axis. a line decreases from 0 to 9.

which function can be used to determine the approximate number of grams of the sample remaining after t hours?

y = 25(0.15)t
y = 25(0.85)t
y = 50(0.15)t
y = 50(0.85)t

see explanation

step-by-step explanation:

since the sequence is geometric there is a common ratio r between consecutive terms, that is

r = 4 ÷ - 2 = - 2

r = - 8 ÷ 4 = - 2

r = 16 ÷ 8 = - 2

the next term - 13 must be incorrect as it should be - 32 for the sequence to be geometric.

the first 4 terms are therefore geometric with common ratio r = - 2

17.08

correct me if i am wrong.

y/x of point b= y/x of point a

step-by-step explanation:

(i got the same question, this was the correct answer.)