Carlos and Ana were asked to find an explicit formula for the sequence -10,-4,2,8,.. Carlos said the formula is f(n)=-10+6n. Ana said the formula is f(n)=-10+6(n-1). Which one of them is right?

Ana is correct

Step-by-step explanation:

Note the difference between consecutive terms is constant, that is

- 4 - (- 10) = 2 - (- 4) = 8 - 2 = 6

This indicates the sequence is arithmetic with n th term ( explicit formula )

f(n) = a₁ + (n - 1)d

where a₁ is the first term and d the common difference

Here a₁ = - 10 and d = 6, thus

f(n) = - 10 + 6(n - 1) ← Ana's formula

the answer to the question is a  

it has the same slope and the same y-intercept.