Write an equation for the nth term of the arithmetic sequence -3,3,9,15 ?

Question

a An = n +6

b An = 6n +9

c An = 6n -9

d An = n -3

Answer 1

okay let's do it this way

n = -3

1st # in that given sequence

are

An=-3+6=3 ok

An=3+6=9

An=9+6=15

obviously the formula

is going to be this

[[[[[[[[[[[[An=n+6]]]]]]]]]]]]]]]

so your answer should be A

once again it should be A

and good luck

Answer 2

And answer is a. Just test it to see:

An = n + 6

Begin with n = -3 (the first number in the given sequence)

An = -3 + 6 = 3

An = 3 + 6 = 9

An = 9 + 6 = 15

So the formula An = n + 6 checks out.

And by the way, if you do the same for the other choices, none of them will work out.

Have a good day!

Answer 3

If an arithmetic sequence has first term a and common difference d, then the nth term is equal to:

a + d*(n - 1)

In this case, a = -3 and d = 6, so the nth term equals:

-3 + 6(n-1) = -3 + 6n - 6 = 6n - 9.

Therefore, the answer is C, not A.