CPM Homework Help : A2C Problem 12-20

A series has $9$ terms, the last term is $18$ , and the fifth term is $6$ . What is the series?

Hint:

Find the sequence that corresponds to the terms of the series.

Hint 2:

$t\left(5\right) = 6 = \left(5\right)a + b\\t\left(9\right) = 18 = \left(9\right)a + b$

Hint 3:

$a = 3 \text{ and } b = −9$

More Help:

Now use the sequence to find the rest of the terms of the series.

Answer:

$\left(−6\right) + \left(−3\right) + 0 + 3 + 6 + 9 + 12 + 15 + 18$