Which of the following choices is the rule for the nth term of the sequence -12,-5,2,9?

Question

A) 7n+19

 

B) -7n+19

 

C) -7n-19

 

D) 7n-19

Answer 1

a_n = a₁ + (n - 1)d, where a₁ = first term, n = number of terms, d = common difference

a_n = -12 + (n - 1)7

a_n = -12 + 7n - 7

a_n = -19 + 7n

a_n = 7n - 19

 

D)

 

Answer 2

Let's see,  the first term (n=1) has the value -12.

 

So, which of the expressions produces a -12 when n=1 ?    You may want to check out n=2, 3, and 4 if you are thorough.

 

Math is easy when you know how to do it!