The amount of money it takes to fill up a gas tank varies directly with the number of gallons bought. it cost $21.87 to fill up a car with gasoline with 9 gallons of gasoline. what is the constant of variation? a) 0.41 b) 9 c) 2.43 d) 21.87

I believe the answer is C. 2.43

y=mx+b is the final answer!   : )

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