Answer:
No solution (read below)
Explanation:
Formula:
a_n = a_1 + (n-1)d
N is the term #
D is the common difference
First, let's find the common difference.
13 - (-15) = 28
Let's see if that checks out.
31-13 = 18
49 - 31 = 18
18 is not equal to 28
Since there is no common difference you cannot find the equation.
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